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What A/B tests would you run to increase the number of messages sent and received on WhatsApp?

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What A/B tests would you run to increase the number of messages sent and received on WhatsApp?

Questions:
Goal” To improve communications and engagement on the platform
Any target audience we want to focus on? – You Choose
Any constraints on the length of the A/B Tests? – No
App/Web? – App
Any other constraints such as cost/Tech? – No
Assumption: we are running this test only in the US – Ok
No distinction between iOS vs Android – Ok

Goal of WhatsApp is to connect the world and encourage interactions in a meaningful way and build relationships.


Users:
Power users – send and receive multiple messages through the day. Use, and are aware of all the functionalities of the product and communicate with a large set of people in various forms of media.
Moderate users – use the product on a need basis – receive more than send and are often not online for large parts of the day. Use it for necessary communications.
Rare users – These users have the app downloaded on their phones, but do not use it often. They receive messages much more than sending and are often not online for days on end as they use other forms for communication with friends and family.

For the purpose, I would like to choose the ‘Rare users’ group for the A/B tests.

Pain Points:
1. Don’t have any common interest from people in their circle
2. Fear of being judged for what they say
3. Discouraged from typing long messages as they often are busy with other things and would rather not spend time typing a lot
4. Often miss out on updates from groups as many people are sending messages – thereby unable to join in conversation
5. Stay in touch with their friends and family using other forms of communication such as Facebook/IG/Other social media apps.

To increase the engagement on WhatsApp – Let’s build a few tests that address these pain points.

Test1: Creation of interest-based groups (LA Lakers group, Fitness enthusiasts group) that users can join and participate
Control group: Does not have ability to search for and join groups
Test group: Has ability to join and participate in interest-based groups
Hypothesis – People who are able to find others with a common interest are able to better relate with each other and hence will be willing to share more on the platform.
Evaluation Metrics:
# total number of ‘interactions’ – Interactions – messages sent and received in groups
# Average numbers of messages sent and received by each user
# Average session time per user
Tradeoffs:
Users may join multiple interest groups and get overwhelmed
They may be silent spectators in these groups.

Test2: Ability for birthday reminders for friends and family (Integration with information on Facebook could be 1 way to get the information).
Control group: Does not get notifications on birthdays for friends and family.
Test group: Receives banner/push notifications about birthdays for friends and family.
Hypothesis: The reminders for birthdays will incentivize people to reach out and wish their loved ones thereby extending the possibility of conversations.
Evaluation Metrics:
# Reminders actioned upon
# Average interaction length based on reminders
Tradeoffs:
Users may have switched off notifications from WhatsApp
Users may not like additional notifications

Test3: AI based conversational system that can predict user’s response and allow for single click-based replies to messages.
The AI system reads the messages received from sender, understand the tone and nature of the conversation and be able to respond in an intelligent fashion.
Control group: Does not have Ai based reply feature
Test group: Is provided with an update on the app that has an AI based conversational system.
Hypothesis: AI based conversational system will increase the communications and interactions among the user base as it negates the users’ aversion of typing long messages.
Evaluation Metrics:
#conversations where AI based comm system was used
# corrections/deviations from predicted text response
#average conversation length post usage of AI based conversation engine
AI based replies as a percentage of overall replies in a conversation.
Tradeoffs:
Users may not upgrade WhatsApp to avail the feature
If there is not enough historical data, then the AI responses may not be useful

There are others as well that we could talk about, but in in the interest of time, I would stay with these tests.

Prioritization of A/B Tests:

Sl No.

A/B Test

Reach

Impact

Cost/Effort

Priority

1

Interest Based Groups

High

High

Low

P0

2

Birthday Reminders

Medium

Low

Low

P2

3

AI based conversational Engine

High

High

High

P1

 

Recommendation:
Based on the above evaluation criteria, I would suggest that we run an A/B test to create interest based groups to increase engagement and communication on the platform.

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Clarifying questions:

Is the intent to increase # of messages sent for a particular user cohort or I can select any? (Any)

Assumption is that this is being done to increase Engagement? Is there any other objective? (Engagement is fine)

Objective: WhatsApp is focussed to build communities as is the mission of its parent Company 'Facebook'. So the objective of this experiment will be to increae user engagement.

User group : Users with medium engagement as they are aready engaged to some extent , so they need slight motivation to engage more.

Experiment : 1 

Push Notifications to remind users when there are some Unread messages.

Hypothesis: Reminders will initate user to send message and then also get replies and starting chain of communication

  • Control Group: Will not get any user notifications
  • Experiment Group: Will get notification when there are unread messages

In both cases, Users with medium engagement with same demograph wil be part of the experiment

Success Metric: 

1. # of messages in experiment group should increase

2. Average time spent by users in Experiment group should increase.

3. Average # of messages per user should increase.

Trade Off:

1. It is possible that users do not sent back the message, but instead call back. One reason that this group is not sending enough messages that they find composing a message hard and they prfer to talk Vs communicate via messages.

2. Notifications do disturb users and many people have a tendency to turn them off

Experiment : 2

UI changes to show a separate tab for Unread messages at the top. It will be in red font, bold and will show the count. On clicking this tab, all unread messages will be filtered.

Hypothesis: This new UI will stand out to the users and will prompt replying back to their friends.

  • Control Group: Will not see any different UI
  • Experiment Group: Will see this new UI

In both cases, Users with medium engagement with same demograph will be the part of the experiment

Success Metric: 

1. # of messages in experiment group should increase

2. # of Unread messages should decrease.

3. Average # of messages per user should increase.

4. Clicks on Unread message tabs should increase over time.

Trade Off:

1. It is possible that users do not sent back the message, but instead call back. One reason that this group is not sending enough messages may be because they find composing a message hard and they prefer to talk Vs communicate via messages.

2. # of unread messages may not truely reflect success of this experiment as it is possible that some messages would have been replied directly 

Experiment : 3

Auto-suggest replies

It is possibe that users do not reply much because they find typing hard. 

Hypothesis: System suggested messages will help users send quick reply from pre-composed message.

  • Control Group: Will not see any auto-suggested replies
  • Experiment Group: Will see auto-suggested replies

In both cases, Users with medium engagement with same demograph will be the part of the experiment

Success Metric: 

1. # of messages in experiment group should increase

2. # of Unread messages should decrease.

3. Average # of messages per user should increase.

4. # of automated messages/# of total messages should increase over time.

Trade Off:

1. It is possible that users still prefer to call Vs send auto messages if user did not get suggested message that user liked

ExperimentsImapctEffort
#1(Notification)HighLow
#2 (UI)MediumMedium
#3 (Auto-suggestion)MediumHigh

To start with, I will go ahead with Experiment #1

 

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​My structure for this AB testing question:

  1. CLARIFY:
    1. Should we be focusing on a specific region: domestic or international? You choose. 
    2. Is there a specific user you want to focus on? Prospect v. current user, etc.? You choose. 
  2. BACKGROUND: WhatsApp is a messaging app that is owned by Facebook. It allows users to send voice and text messages, make voice and video calls and share images / videos, etc. It is generally used on mobile devices but does have a desktop component as long as the user's mobile device remains connected to the Internet while they use the desktop app. It is popularly used to make international messages and is used in a variety of countries, including the US, India, Brazil, Indonesia, etc.
  3. GOAL: The goal of the AB tests will be to increase the number of messages sent and received on WhatsApp. 
  4. USER GROUPS: There are two types of user groups we can focus on. For these AB tests, I'd like to focus on existing users.  
    1. Prospects: Have never used Whats App. Would need to focus on bringing them into the platform to increase the overall user population / messages being sent and received.
    2. Existing Users: Current users of WhatsApp though usage may vary from low usage to power usage. 
  5. BRAINSTORM AB TEST IDEAS
    1. Push Notification Reminders: Send push notification reminders to select group to get them to engage in WhatsApp. 
      1. Hypothesis: Users who receive push notification reminders to use WhatsApp will send more messages. 
      2. Experiment
        1. Control Group A: Does not receive any push notifications. Would have to be a similar group to Experiment Group B (ex. same region, age, etc.)
        2. Experimental Group B: Receives push notifications to get them to engage in the app. For example, "Don't forget to check in with your friends using WhatsApp." 
      3. Success Metrics:
        1. Average number of messages / user sent by Group B v. A
        2. Total messages sent by Group B v. A
        3. Time between next message sent and push notification (ex. did users in B send a message right after they received the push notification)
      4. Trade Offs
        1. Users may have turned off push notifications from WhatsApp
        2. Users may not enjoy additional "Marketing" like notifications 
    2. Personalized Recommendations: Send personalized notifications to users to remind them to check in with someone they may have lost touch with
      1. Hypothesis: Users who received personalized notifications will use WhatsApp to send more messages
      2. Experiment
        1. Control Group A: Does not receive any personalized notifications. Would have to be a similar group to Experiment Group B (ex. same region, age, etc.)
        2. Experimental Group B: Receives personalized notifications to get them to engage in the app with a person they recently lost touch with. For example, "You last messaged Person X 3 weeks ago. Do you want to check back in with them?"
      3. Success Metrics:
        1. Average number of messages / user sent by Group B v. A
        2. Total messages sent by Group B v. A
        3. Number of messages received by average recipient in Group A v. recommended recipients in Group B 
      4. Trade Offs:
        1. Users may deliberately not want to contact someone (ex. recent ex, friend they had a fall out with, etc.). Would need a strong algorithm to determine if a person should be a recommended recipient. 
        2. Users may not want WhatsApp "reading" their texts. Privacy concerns. 
    3. Connection Marketing Campaign: Create an email marketing campaign around maintaining connections via WhatsApp.   
      1. Hypothesis: Users who receive the marketing email will engage with WhatsApp more / send more messages. 
      2. Experiment
        1. Control Group A: Does not receive any email. Would have to be a similar group to Experiment Group B (ex. same region, age, etc.)
        2. Experimental Group B: Receives email encouraging user to engage with WhatsApp. Email could focus on how WhatsApp helps you maintain connection especially when everyone is virtual in COVID. 
      3. Success Metrics
        1. Average number of messages / user sent by Group B v. A
        2. Total messages sent by Group B v. A
        3. Clicks on email (assuming there is a link in email that links to WhatsApp)
      4. Trade Offs:
        1. Not every user will click email / open WhatsApp
        2. Emails could go to Spam. 
        3. Users may not like receiving marketing emails from WhatsApp. Could be seen as an annoyance / deleted without being read.
    4. Business Partnership: Partner with an ecommerce business to get them to use WhatsApp as a vehicle to contact their buyers for advertisements, notifications of delivery of items, etc.
      1. Hypothesis: Buyers from businesses who have the opportunity to sign up for WhatsApp notifications will receive more messages.
      2. Experiment
        1. Control Group A: Does not receive any option to sign up for WhatsApp notifications. Would have to be a similar group to Experiment Group B (ex. same region, age, etc.)
        2. Experimental Group B: Has the ability to opt-into WhatsApp notifications on business website and during check out. (For example, sign up for notifications of sales via WhatsApp or notifications of delivery of your parcel via WhatsApp.)
      3. Success Metrics:
        1. # of people / % of people in Experimental Group B that sign up for notifications
        2. Average number of messages received by user in Group B v. Group A
      4. Trade Offs:
        1. Experimental Group B is limited in size. Group must sign up for notifications on third party site. Less control over getting them to sign up.
        2. Much more complex test because of third party than quick AB test via WhatsApp app. 
        3. Higher cost to set up automated notifications of things like status of delivery. 
  6. PRIORITIZE AB TESTS:
    1. TestImpact to GoalCost to WhatsApp
      Push Notification RemindersHighLow
      Personalized RecommendationsHighMedium
      Connection Marketing CampaignMediumLow
      Business PartnershipLowHigh
  7. RECOMMENDATION: Based on the prioritization, I would choose to run an AB test during which we send generic push notifications to users to get them to engage in WhatsApp. Given that WhatsApp already has push notifications built, running this test should be fairly low cost.  
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  • Free messaging platform with a large user base globally 

  • Key features

    • 1:1 or group chats, voice or video calls

    • Save messages, take pictures

    • Basic profile - view last login of users

  • Typical user journey

    • Sending from other platforms (e.g. google photos, dropbox)

      • User selects photo to share in google photos/other app

      • Export to whatapp

      • Select contacts to send to

    • In-app sending

      • Open app

      • Tap chat icon 

      • Search or scroll through contacts

        • Default display is by last contact

      • Send message

    • Receiving

      • Notification of message

      • Click on notification

      • Read message

  • Objective: increase sent and receive messages

  • Ideas for tests

    • H1: seeing contacts grouped by frequency of sending/receiving may prompt more messages

      • Test: UI to display contacts grouped by frequently sent or “it’s been awhile” categories

      • Control: Contacts grouped by last sent (as is)

      • Success: increase in # messages sent or received/user in 1 week

      • Tradeoff: Increased friction in sending / one additional tap needed, could slow users down in sending messages

      • Impact: L 

      • Cost: M

    • H2: Adding in a push notification to prompt send messages to groups/contacts

      • Test: Opts in to receive notification to prompting to send a message to a group/contact that hasn’t been contacted in awhile

      • Control: No notification option (as is)

      • Success: 

        • Increase in sending

        • Opt in rate for notifications

        • Click through rate from notifications

      • Tradeoff: too many push notifications cause user to abandon app or cause users to diable notifications which we may want to use for other functionality

      • Impact: L

      • Cost: L

    • H3: Prompting users to create specific types of groups -  family group, friend group

      • Test: Receive prompt during onboarding to create two types of groups - family and friend group

      • Control: As is

      • Success: increase in messages sent

        • # of groups created

      • Tradeoff: Potential privacy concern - labeling as a family/friends - could cause users to be wary of app

      • Impact: H

      • Cost: M

    • H4: Sharing data on typical uses “How you compare to others - e.g. typically people have 4 groups or “typical users send 5 messages a day” - inspire people to send more

      • Test: See a pop up upon login - typical users send x message/day

      • Control: As is

      • Success: increasing sending/receiving

      • Tradeoff: users who typically send more than average could reduce the  number of messages typically send as users tend to gravitate towards the norm

      • Impact: H

      • Cost: L

    • H5: Set Reminders for sending messages to certain contacts - e.g. “Set reminder to send message to x in x timeframe”

      • Test: New reminder feature

      • Control: as is

      • Success: increase sending / receiving

      • Tradeoff: putting contacts on the back burner / e.g. remind me in 3 mo may actually decrease frequency of contact

      • Impact: M

      • Cost: M

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About WhatsApp:

Whatsapp is an application owned by Facebook which allows messages and VoIP (Voice over IP address to users.)

Objective:

Increase the number of messages sent and received on it.

Assumptions:

The AB tests would be specific to the mobile application without interference of any external forces.

Hypothesis:

1.       Shorting contact list by the last seen time i.e. A person who is online now will be on top irrespective of the person who was active 1 minute before.

2.       In recent updates of “STATUS”, shows the “PROFILE PIC CHANGES” as well.

3.       To forward any photo or URL from, list the “GROUPS” on top and give the option to select “ALL Group” as well after shorting the users based on the number of active users and their active time.

Experiment:

1.       Show the top five active users who were active recently.

2.       Disappear the profile pic changes status in 12 hours irrespective of 24 hours for other status.

3.       The users can forward only photo or URL in all groups simultaneously.

Criteria for success:

1.       Active users suggestion to conversation rate

2.       Profile pic suggestion to reply rate

3.       No. of photo/URL forwarded to the number of replies received on that from the other members.

Trade-off:

1.       Users might start avoiding sending messages to the person who was active a long time ago.

2.       Introvert kind of users may start avoiding changing the profile picture.

3.       Users may start doing viral fake news or photos to many people that can create disturbance in society.

 Prioritization:

Prioritize

Impact

Implementation effort

I.                     Profile pic changes status

Medium

Medium

II.                   Short Contacts

Medium

High

III.                 Forward photo/URL

High

Medium

 

 

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Things that you did well:

The structure that you followed was easy to follow.

Areas of improvement:

  1. Connecting your hypothesis to the objective will help you carry the point more effectively
  2. Explaining your experiment with more detail will helpus understand your take more efficiently
  3. The criteria of success is not clear. It seems to be stopped midway. So try explaining the criteria more and stating how you expect it to move will add value to your take and make it easy to understand
0
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Clarifying Questions
1)While testing you want me to focus on any particular region? --> you can choose anything
2)Do You want me to focus on any particular region? -- > you can choose anything
 
About WhatsApp
WhatsApp is the biggest messaging App in the world with 2B+ downloads.  Help users to share data in an easy and reliable way. Users can send text, photos, links, audio, and video messages. User can share their status. Audio and video call facilities there.
 
Goal
Increase the number of sent and received messages.
 
User persona
College and School students: Students use Whatsapp to connect with friends. more tech savi so adopt new features easily.
 
Solution
Note: In all cases, Group A is a control group and Group B is an experiment group
1)Push notifications: Send push notification reminders like someone waiting for them or you lose touch, more personalized notification.
Metric
->no of messages sent per user in Group B vs Group A
->no of total messages sent in Group B vs Group A
->time difference between message send and push notification
Trade-offs
->User may turn off notification
->User may be irritated by notifications so uninstall WhatsApp
 
2)More WhatsApp Business API integration: Encourage more businesses to use Whatsapp for their promotional campaign so users got more engaged with it and send more messages.
Metric
->no of messages sent per user in Group B vs Group A
->no of total messages sent in Group B vs Group A
->time difference between message send and push notification
Trade-offs
->User may turn off notification
->User may be irritated by notifications so uninstall WhatsApp
 
3)Automatic reply suggestion: Users get automatic text based on AI recommendations that save user time and also increase no of messages.
Metric
->no of messages sent per user in Group B vs Group A
->no of total messages sent in Group B vs Group A
->no of message user used auto-suggestion feature/ no of a message sent
->no time user clicks on auto-suggestion daily
Trade-offs
->replies are not good so users never click on that
 
4)Special day reminders: WhatsApp sends notifications for special days like birthdays, anniversaries, and others.
Metric
->no of click on a reminder notification
->time difference between next message and reminder
->no of messages sent per user in Group B vs Group A
->no of total messages sent in Group B vs Group A
 
Prioritization using the RICE framework, I would like to prioritize Push notifications and Special day reminders.
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Questions:

 

  • Per which timeframe do we want to maximize? per day or per year?

  • Is it specific to a certain Geo or user group (e.g. less active users)?

  • Why are we looking to increase the number of messages?

 

Product Description:

 

Now, let’s talk about the product: WhatsApp is a messaging app that allows users to message their contacts. Users can reach any other, as long as they have their phone number. Users can also call and videocall, send images and videos, share location, and it does show (if user enables it): last access time and if the message was viewed or not. 

The app is completely free. 

 

Goal:

Increase messages sent as core part of the product itself. The objective is to increase usage and time spent in the app for existing users.

 

Hypothesis:

There are users less active than others; thinking about the reasons, these could be:

  • Users prefer calling

  • Users friends do not have Whatsapp

  • Users prefer Social Media chat because they can reply to friends posts and initiate the conversation in this way

 

Prioritize:

For the first test mentioned, we would first need to collect some focus group data to verify how this behavior can be changed or onboarded in Whatsapp. It will anyways maybe not affect the metric. The third one, as Meta, Whatsapp parent company owns other social media is mostly self-cannibalizing users, bringing them from one product to another. 

The second hypothesis is the most appealing to test, as it would bring in new users. 

 

Test:

In this case, we can run a promotion to invite a friend to 50% of the less active user base in exchange for a coupon. 

We can define the less active user base as users with less than 20-30 messages sent and received per week. 

The test has to be run for a period of two weeks, to create some urgency while letting users the time to sign in. 

 

The metric to observe are:

  • # new users

  • # messages per users that signed up (new users)

  • # messages per users that invited their friends

  • # friends invited

 

per week. 

 

Other metrics that can be affected are: 

 

  • increase in the number of non active users (if the user invites friends just for the reward)

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1) Describe the product

Ok, so we are talking about Whatsapp, which is the messaging app where people add one another using their phone numbers, and can, in addition to message, share videos, links, pictures, etc. They can also make calls and video-calls. Is that right?

2) Clarification

  • We are focusing on Whatsapp for regular users, not Business Whatsapp. Right?
    • Right.
  • Are we focusing on specific user, by age for instance, or geographic region?
    • Across the globe.
  • We are also focusing on the mobile experience, right?
    • That's right.
  • Another important aspect here. There's sort a delay to receive messages on Whatsapp. So, for the purpose of this exercise, I will just assume that if you send an message you receive it. Does it make sense?
    • Yes, it does. You can go with that.
  • Lastly, we are not interested in increasing the visualization of those messages for now. Is that fair enough?
    • Yes, that's make sense as it would be another problem.
3) Define Goal/Objective
 
Well, Facebook's goal is to connect and bring people together all over the world. So, it makes sense to increase the number of messages being sent and received over Whatsapp, meaning people build stronger relationships over time for instance.
 
Therefore, I think we can establish "making it easier and faster to send messages" as an objective to reach our goal of increasing messages.
 
4) Brainstorming Ideas/Hypothesis
  • Change the format of the button to start conversations
    • Hypothesis: making it more visible, users should start more conversations, thus increasing the number of messages
  • Notifications like "You have not responded last message of John".
    • Hypothesis: remembering users to send messages can also increase its number
  • When you open up "new chats", you would find a set of recommendations based on recently added contacts, most recent, quite not talkeed for while, etc
    • Hypothesis: making smarter suggestions should also motivate users to send more messages
5) Prioritization of Ideas
I would go for a) and b) because they are small changes and faster to run tests. As for the c), even tough we could build a simple recommendation, it will need to do some coding.
 
Between a) and b), I would go for a), as for b) it needs a sort of permission to receive notifications, and it could reduce the efficiency of our test.
 
Therefore, moving with "Change the format of the button to start conversations".
 
6) Design Experiment
  • Control group (A) would continue to see the same format to start a new chat
  • Test group (B) would see another format to start a new chat. For the first test, I would make it bigger and/or make it clear that it's for starting a new chat. So, it shoud be bigger and have something written below or next to it "Connect with someone".
  • Segmentation: I would not segment per type of user, since I understand we want to roll-up such change accross the globe, therefore I would try to make it as homogenous as possible.
  • I would make sure to split the groups using "user_id" to stick with the same user accross platforms and sessions, avoiding as much noise as possible.
  • I am assuming Facebook has a internal or external platform to perform A/B tests, so I would input the basic rules for this test, such as test power of 80% and let the calculator gives the time for test and size of population.
  • Given the size of user base and interactions per day, I think this test would be very fast to complete.
7) Metrics
  • Success Metrics
    • Avg number of new chats started per user_id
    • Avg number of clicks on the new button per user_id
    • Avg number of messages send/received per user_id
  • Explainable Metrics
    • Avg number of clicks to close new chats tab per user_id
  • Guardrail Metrics
    • Avg session time per user_id
8) Trade-offs
  • Some users might just be curious about the new size and format of the button, therefore not completing the action to send new messages.
  • Depending on the size, it might break a little bit the UX and design of the home page. Therefore we wouls also need to decide on that.
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Describe the product

WhatsApp is a messaging platform where a user can send messages to other user in form of text, image, video, location etc. They can also place an audio/video call to the people. Status can be set by the users as well.

Objective

Increase the number of messages sent and received on WhatsApp.

User Types

  • Casual User: Who sends less than 15 messages/day, receives less than 10 messages/day

    • New User: Who has newly joined WA in last 7 days

    • Existing User: More than 7 days

  • Moderate/Power User

Assumptions

  • We are taking mobile app in consideration

  • Will run AB tests for casual user who has newly joined

  • Target region is India

  • Direct one to one chat or to group

User Journey

StepPain PointImpact on User
Opens the app- 
Clicks on new message button or go to an existing chat- 
In case of new chat button, see the list of saved contacts and select one of them to start chatMay not have enough contactsLow
Once chat appears, types in a text or attachment or record voice and send- Not comfortable in typing English
- Don't know how to send attachment or record voice
High
 

Hypothesis

  1. Show the test users pop up to select typing language

    1. Experiment:

      1. Control Group A: A group of users have the same features of Whatsapp with no change

      2. Test Group B: When a user goes to a chat, for one or two times(if not selected in first), show a popup asking to select a language that the user is comfortable for typing. Once selected, the keyboard should turn to that language. There should also be an option to reverse back to default

    2. Metrics:

      1. of messages sent/day/user/group A & B

      2. Avg # of messages sent/day/user/group A & B

      3. of users who select the typing language in first time and the ones who discard it

    3. Trade offs:

      1. Language selection popup might irritate the user

  2. Highlight the attachment button

    1. Experiment:

      1. Control Group A: A group of users have the same features of Whatsapp with no change

      2. Test Group B: Shake the attachment button periodically for a user who has not sent any attachment till now.

    2. Metrics:

      1. Number of attachments sent /day/user/group A & B

      2. Avg # of attachments sent/day/user/group A & B

      3. Time taken for a user in Group B to click on attachment button, when online in a chat

    3. Trade offs:

      1. It might distract the user or irritate him/her

  3. On chat list page, show bar to send "Hi" to user's currently active friends

    1. Experiment:

      1. Control Group A: A group of users have the same features of Whatsapp with no change

      2. Test Group B: After search bar, show a bar to the user to send "Hi" to their currently active friends. On clicking it, in a popup, user can see list of currently active friends, select multiple of them and send "Hi" as a pre-defined template.

    2. Metrics:

      1. of messages sent/day/user/group A & B

      2. Avg # of messages sent/day/user/group A & B

      3. Number and % of users in Group B who clicked on the bar

      4. Number and % of users who opened the bar and sent the template in Group B

      5. Number of template messages sent via bar in Group B

      6. Avg number of template messages sent via bar in Group B/user

    3. Trade offs:

      1. It will lower the starting position of chat listing by occupying space

      2. After 1 or 2 try user might feel it unnecessary

Priortization

TestImpact EffortPriority
Show the test users pop up to select typing languageHighHigh2
Highlight the attachment buttonLowLow3
On chat list page, show bar to send "Hi" to user's currently active friendsHighMedium1

So, I would like to go with experiment 3 after priortization

 

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Interesting and fun question since I do use Whatsapp but I also wonder why people just don't like Whatsapp. So let's get an understanding of Whjatsapp that I have and verify I am not missing something.

Whtsapp is a chat engine that's free to use and texting internationally on it doesn't cost anything. Unlike iMessage though, it does use data. While iMessages now have a feaTure to respond to a specific message someone sent Whtsapp has always had that feature. You can also delete messages send on it. Creating groups on it is great because you can easily add / remove people and add more admins to it. 

Interviewer: Yes good understanding.

Me: Ok to think of where the problem may like might be good think howI use the product. (sure go ahead). I add someone in my contacts and then go to Whtsapp to message that person. I then get check mark that tells me if teh person read the message but that's only true if the person kept that feature on in their settings. When I get a new message, I get a # of messages icon on top of the app icon. I long press a message to delete it for me or everyone. 

I thikn personally the frustrating aspect for me on Whtsapp has been two things:

1. I have to add someone to my contacts list before I can text them on Whtsapp. Many times though, you don't want to add people. Such is especially the case when you are creating a community based group such as for PMExercises let's say and you don't know many people but you have to add them individually to your phone book for you to add them. 

I think if we were to think of minor changes, this alone could make a big impact to our objective of incresing engagement per say as it relates to "sending and receiving more messages". 

Is it ok if I proceed to evalute how we may test this change or would you rahter have me think through some more improvements? (this is fine).

Me: Great. As the pain point I presented and implied fix I suggested, I believe that enabling me to just type in a person's name on Whtsapp whereby Whtsapp hosts every user in its cloud should make it more compelling for me to want to use Whtsapp to message that person instead of other means, since I don't have to add him/her in my address book. 

To test this, I think we should randomly pick a control group and a exeperimental group. Since the question is around "increasing # of messages" can I safely assume that we are looking at existing users of Whtsapp and not acqusition of new customers? (yes)

Great our control group should be of those who aren't as active and it should be a randomly selected set.  I would likely run this test for a month and then see the results. While I pick timeline of test somewhat randomly, I think while Whtsapp has enough users and could possibly get decent data wtihin a week, I also think 1 month will give ample time for new feature news to spread and more people getting onboard and seeing their consistent usage, thereby retention. Here I feel, engagement and retention are tied to each other hence 1 month is likely going to help us get a better guage of success achieved by this feature. Any quiestions? (no)

Ok, I do want to mention that this appears to be a huge change since if people have to enter contacts in their phone book we are assuming FB doesn't have anyone's contact but I hardly believe that to be the case. Even if we don't, FB can easily retrieve needed numbers from users use of Whtsapp. Implementation here is easy and impact will be big for FB if we gain engagement / retention from users. 

After a month, I would measure # of messages received and sent from users in each group. While we were only evaluating current users, it be also interesting to see # of net new users gained on Whtsapp vs. in the past in a month. But I would focus the 1st metric presented to decide if we should proceed with this feature. The one big downside I see here is that there are bunch of people with same names so this may cause huge complications in identifying the correct person to text to. Also, ton of messages couldbe sent to wrong people leading to harassment issues. Thinking of this, I honestly doubt this would be a successful test so I think we should want to be very limited in # of users we text this featurte on. Maybe, after randomly chosing people we should first ask them if they want to be part of beta testing users with presented downsides but not tell them why we are conducting this test. 

Any questions? (no....thank you for your time).

 

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Description:

Whatsapp is a product under Facebook family. It is a product throughwhich one can connect with people through text messages, voice messages and as well as do Voicecall and Videocall to eachother. One can also share pictures, videos with other people. All this happens over the web. It also has a web component that a user can use through Computers/Laptop provided the mobile is connected to the internet as well.

Objective:

The objective here is to increase the number of messages sent and Received on Whatsapp.

User Segment -Based on Messages sent/Received:

  1. Power Users
  2. Medium Users
  3. Low Users
Of this, I would like to prioritize and focus on the Low Users as the other two categories are already sending and receiving multiple messages a day.
 
Brainstorm A/B Tests:
  1. Notifying users on new status updates
    1. Hypothesis: Users notified on new status updates would interact with them through messages.
    2. Experiment:
      1. Control Group A: A group of users have the same features of Whatsapp with no change 
      2. Experiment Group B: The Group of users who are similar to Group A in terms of all demographics, receiving notifications when a contact of theirs upload a new status. The notification can be phrased short and sweet with help of the Content Team.
    3. Success Metrics:
      1. Ratio of Sent messages: Received Messages WoW
      2. # of messages interacted as a reply to status
      3. CTR to Notifications
    4. Trade Offs:
      1. Notifying everytime a user uploads a story might irritate the user and thus might affect the CTR of notifications of WhastsApp in general. Thus, as a counter metrics, We shall keep a track on CTR to Notifications
  2. Changing the Unread Chats Number that is shown near Chats bar to Number of messages Unread Overall.
    1. Hypothesis: Users might react soon as the count will increase at a faster rate.
    2. Experiment
      1. Control Group A: A group of users have the same features of Whatsapp with no change 
      2. Experiment Group B: The Group of users who are similar to Group A in terms of all demographics, is shown # of unread messages in the chat bar.
    3. Success Metrics 
      1. Ratio of  Sent messages: Received Messages WoW
      2. Time Taken in reducing the unread messages to zero from when the unread is 1 WoW
      3. Total number of messages sent per  Week
    4. TradeOffs
      1. Few users might take this in the wrongway, i.e, they would wait for a particular free time to react to the messages as the number already is super high. This, thus will reduce the messages sent and received. To keep a check on this, Time Taken metric can be closely watched.
  3. Showing stats on # of messages sent per day for the groups separately
    1. Hypothesis: The group members might take this as a competition to send messages and interact more.
    2. Experiment:
      1. Control Group A: A group of users have the same features of Whatsapp with no change 
      2. Experiment Group B: The Group of users who are similar to Group A in terms of all demographics, are shown the new stats in the Groups along with participants.
    3. Success Metrics:
      1. Ratio of Messages Sent:Messages  Received
      2. # of people checking the stats
    4. Tradeoff
      1. The competition will be shortlived. 
Prioritzation:
A/B TestImplementation effortImpact related to Goal
Notifying users on new status updatesEasy as Wp is already notifying users for messagesHigh as the notification will help as a new way of initeracting 
Changing the Unread Chats Number that is shown near Chats bar to Number of messages Unread Overall.Easy as Wp is already doing this in a wayMedium as this might fireback as well

Showing stats on # of messages sent per day for the groups separately

Medium as Wp does this already in a way under settings menu. However placing it attractively in the Group Menu will be a bit difficultLow as the competitive nature this feature creates will be a short-lived one

So in summary, the A/B test that I would put into experiment will be Notifying users on new status updates.

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