Click the below image to access the interactive prototype.


Water Drink Reminder is an app for Android and iOS that “reminds you to drink water every day to keep you hydrated.”

Design Optimization Goals

The following goals were informed through usability testing with five participants:

• Reduce user confusion with navigation

• Improve efficiency of use with less taps

• Optimize drink selection controls


I have no affiliation with the Water Drink Reminder mobile application with the exception of being an unpaid user.



Before Design Optimization


After Design Optimization

I validated the optimized redesign with usability testing to confirm that users are able to correctly select a drink with one tap, eliminating the confusion of to buttons and a modal window. 100% of users were able to correctly select a drink on their first attempt.

Users were able to modify their drink with less taps compared to having to access a modal window in the base design.

Finally, users were able to easily delete a drink without having to again rely on a modal window and exploration for how to delete the item.

Usability Testing and Design Modifications

In order to build and maintain healthy habits, it’s critical for users to have a positive experience with digital health tracking tools used for a specific purpose.

My intention with usability testing and design modifications was to determine foundational issues impacting the customer’s motivation to use the app on a daily basis.

My Role

This project was completed independently to advance my user experience skills.


I developed a proto-persona to support the research and design process. Sam, below, is an assumption of a specific user of the Water Drink Reminder app, which may be validated with a longer project timeline and in-depth user interviews.

Job Story

The purpose of a job story is to establish an informed design process that takes into account the user’s situation, motivation, goal, and intended outcome. In the context of using the Water Drink Reminder app, the job story helps identify specific scenarios to help with the discovery of pain points and potential design resolutions.

Sam’s Job Story

Since I have to manage my kidney disease on a daily basis, I want to be able to easily track and log my fluid intake to prevent painful symptoms and improve my stamina at my busy office environment.

Guerilla Usability Testing

Guerilla usability testing supports selection of random users in a short timeframe, with a constrained budget, and elimination of participant travel burdens.

Users were randomly selected in the SOMA neighborhood of San Francisco and at a shopping center in Palo Alto. All usability testers gave verbal and written consent to be recorded. All users were confirmed to have never used Water Drink Reminder.


Data capture and observations are based on five distinct users. Nielsen Norman Group suggests that no more than five usability testers are required due to reaching a saturation point of observing the same issues and behaviors replicated as the testing surpasses the third user.

Testing Scenarios and Tasks

Testers were provided the following scenarios with the goal of evaluating behaviors attached to each underlying task.

Each scenario supported a task to evaluate fundamental functions that new and existing customers would use at a high frequency when interacting with the app.

Sample Scenario

Since this is the first time you’re using the app, please take a moment to review what you see displayed. Please show me what you drank for breakfast today.

Sample Task

Add the correct drink type (e.g., coffee, water) and approximate volume to reflect true drink from today’s breakfast.

Task Flows

Development of current and optimized task flows are included in the design process to inform the design research and ideation processes. The current task flow for adding a drink to today’s log require a choice of two, with one option requiring more decision-making.

Current: Add drink to today’s log

Users are required to make a choice from two selections to add a drink to today’s log.

Optimized: Add drink to today’s log

I optimized adding a drink to today’s log by relocating the carousel drink menu from a modal window to the main dashboard, effectively eliminating the need for a modal. It prevents the user from having to make a decision from two options (i.e., select default drink or open modal window).

Pain Points

Pain points were determined through observation of user behaviors, statements, and verbal feedback from filmed testing.

Sample Pain Point and Observation

Pain Point: Adding Drink to Today’s Log

Users unable to efficiently identify and select the drink they want to record. Users were required to either select from a hidden menu or accidentally repeated the default selection.

Observation Examples

• User states, “am I doing this right?” while struggling to identify how to add a drink.

• Two users went to ‘alarms’ section instead of correct navigation to add drink.

• User adds default drink from previous selection that doesn’t match their reality (i.e., coffee auto generated when they meant to add water)

• Responded, “no, I didn’t have none of that.”

• User selected navigation drawer in attempt to add drink.

Final Remarks

This case study offered an abundance of opportunities to consider in redesigning multiple aspects of the Water Drink Reminder mobile app. The user research and design process reinforced that focusing on prioritizing fundamental aspects of an application can afford significant results in removing barriers to usability and engagement.