For the design question the interviewer will evaluate you on the following points:

• 1. How well do you identify your users and their pain points?
• 2. What are the specific use cases that you are focussing on?
• 3. How do you prioritize and recommend the final solution that solves their pain points?
  

To have a structured approach for the design questions, I adopted the CIRCLES method (Ref. Decode and Conquer by Lewis C. Lin)

The steps of this method are:

C — Clarify. Ask clarifying questions to narrow the scope.

I — Identify the users/customers as personas like food lovers, soccer moms, etc.

R — Report on the user’s needs (use cases). A use case is an activity that a user would like to do relative to the product.

C — Cut through and prioritize the use cases based on some attributes (revenue, customer benefit, complexity).

L — List solutions.

E — Evaluate the tradeoffs of your solutions.

S — Summarize:

State which solution you would recommend.

Recap what the solution does and why it is beneficial.

Explain why you prefer this solution.

Interviewer: Design an alarm clock for the people with hearing disabilities

Interviewee: Before starting, I will ask some clarifying questions: What people are you targeting i.e. their location or some other attributes that you can share? And regarding the alarm clock, are you referring to a physical alarm?

Interviewer: You can assume the people have no hearing ability and you are free to assume how the alarm looks like.

Interviewee: Ok. I will list down my assumptions first (These clarifications help you narrow down the scope of the problem initially)

• 1. The users do not have any hearing abilities
• 2. As a PM I will focus on 2 core jobs - [a] The user must be notified by the alarm and [b] The user must be able to use this device for his / her daily activities
• 3. I assume that the zero hearing ability users have no other disability that affects their sight/speaking ability/arrests their movement. All these users can see the time, set the alarm but won’t be able to hear the conventional alarm ringing.
  

For the user personas, I am dividing my users based on age. This will help me understand what their daily life looks like and based on the external care they are getting.

Interviewer: Sounds good.

Interviewee: Ok so these will be the user personas and I will highlight their use cases as well.

• 1. Working Professionals (25-60 years; assuming a retirement age of 60). They may or may not be accompanied by caretakers for most of their day. And they need to wake up, set timers while cooking, set meeting reminders/daily household chores
• 2. Children who are <18 years are taken care of by their parents at home and by teachers / friends at school
• 3. College students (20-30 years). They are either living under special care or living on their own in hostels. If they are living in special care then they will be under a caretaker, else they will use an alarm to wake up, set college task reminders, and figure study routines
• 4. Older people (>60 years) will generally have a caretaker to take care of them. They may use it to set their medication reminders.
  

Interviewer: So which use cases are you focussing on?

Interviewee: I will focus on working professionals and students. They are mostly on their own and an alarm clock will not only help them wake up but also assist them with their daily chores. (Tying it to the jobs that I want the solution to complete).

The two use cases will be

• 1. Setting reminders for meetings, study routines, class timings
• 2. To wake up from sleep.
  

Interviewer: Ok. You can go forward with your solution.

Interviewee: 3 types of stimuli can be used to notify a person i.e., visual, audio, and touch. 

• 1. Visually, it may not be possible to disturb the user as it either requires the object to be in sight of the user or the user must be before a screen
• 2. Audio stimuli are not helpful as the person doesn’t have hearing ability
• 3. Touch stimuli, for example, vibration, will be able to notify the user.
  

The solution consists of 2 parts, a mobile app and a watch that can vibrate based on the alarm set. Alarms can be scheduled using the app or the watch itself.

Watch features:

• 1. It will have a small non-touchscreen (to keep the price low) and a chargeable battery. It can connect with mobile via Bluetooth
• 2. The user can set the alarm through the watch itself, but while setting it using the app, the watch needs to be connected to the phone via Bluetooth. Once set, the watch will save the timings. This way there is no need for the watch to be near the mobile all the time
• 3. Since the watch will be in the user’s hands for the whole day, the strap must be of rubber or fabric. Extra straps can be provided in the package for the user to change regularly based on their comfort.
  

Mobile App features:

• 1. The user can set reminders, timers, and alarms just like a conventional alarm app
• 2. To help the user with his daily activities, the app will have useful templates like classroom timetables, study timetables, and medication timetables where the user can fill the timings and set alarms. They can also create custom templates
• 3. The vibration pattern and intensity can be changed indicating the activity type
• 4. The app will have a Google Calendar integration. The watch when connected to the phone via Bluetooth will vibrate for reminders and meeting notifications.
  

Interviewer: So what if a person doesn’t like wearing a watch while sleeping?

Interviewee: Having a watch on one’s hand for the whole day or while sleeping may be uncomfortable for some people. The strap material plays an important role here in providing comfort. To take care of this aspect, I have provided a range of strap materials with the watch.

Interviewer: What are the other shortcomings of your solution?

Interviewee:

• 1. The watch may miss calendar reminders if not connected to the phone via Bluetooth
• 2. The watch needs to be charged. It may also get damaged due to water
• 3. Watch memory space needs to be optimized to store the template and alarm data.
  

Summary - People with no hearing ability can easily search for their phone/watch and set the alarm. The only pain they face is to be notified by the alarm. Vibrations are the optimum way to notify our users (people with hearing disability). The watch + app solution does the following jobs successfully:

• 1. Notifying the user through vibrations generated by the watch
• 2. To support the user in their daily chores, the app provides a feature of templates for creating timetables and helps them design their whole day.

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PM School helps with intense prep around Design and other Product Improvement questions in the PM School program modules.