BillBro

When traveling or going out in groups, managing shared expenses often becomes chaotic. People typically rely on manual tracking, juggling between spreadsheets, chats, and receipts. This process is not only time-consuming but also prone to mistakes.

We identified three major challenges:

• Difficulty collecting and organizing transaction receipts.
• Difficulty calculating and assigning complex bills, especially those including tax, discounts, and shared items.
• Difficulty tracking payment statuses among group members.

BillBro was created to eliminate the friction of splitting bills. By allowing users to scan receipts, add expenses manually, and track who paid for what, BillBro simplifies the process of dividing costs.

The app’s trip-based structure enables users to group related expenses, view an automatic summary, and see each member’s balance in real time. For more casual use, the single-bill feature lets users split one-time payments instantly — perfect for quick hangouts or shared meals.

Through clear organization and intuitive design, BillBro turns what’s often a frustrating process into a seamless experience.

The design process began with identifying user pain points through interviews with several people who often travel or go out with friends, family, or colleagues. The goal was to understand how they currently manage shared expenses and where existing methods fall short.

Key findings from the interviews:

• Manual management is still common — Most participants preferred using spreadsheets to record expenses, noting who paid for what, individual consumption, total costs, and even exchange rates when traveling abroad.
• Multiple tools are used simultaneously — Many relied on a combination of notes apps, WhatsApp messages, and even PDF documents to keep financial records organized, showing a lack of a single integrated solution.
• Meticulous personal tracking habits — Participants often remembered each person’s order manually, took photos of receipts after paying, and reviewed credit card transaction emails for better accuracy.
• Communication happens through chat apps — To settle payments, users typically reached out to friends individually via messages or created group lists where members could tick off their names once payment was completed.
• High effort for accuracy — Despite being time-consuming, participants invested considerable effort into ensuring expenses were correctly tracked and fairly divided — revealing a strong need for a more efficient, automated approach.

These findings revealed that users often rely on fragmented manual workflows that are time-consuming, inconsistent, and prone to human error. This insight led to defining the core user goal:

“ Help a group of people calculate, assign, and track their bills while traveling. ”

To better frame the solution, a user story map was created to define user roles and needs:

“ As a traveller in a group, I want to calculate, assign, and track our bills while travelling, so that I can manage the group’s expenses faster and easier. ”

Supporting User Stories:

• As an Expenses Manager, I want to collect receipts and recap group transactions easily so I can keep a clear expense history.
• As an Expenses Manager, I want to generate and edit complex bills (tax, discounts, sharing) accurately so I can assign the correct amounts to each person.
• As a Person in Debt, I want to get reminders and see detailed payment information automatically so I won’t forget and can pay my debt easily.

From these user stories, the main pain points identified were:

• Difficulty collecting and organizing transaction receipts.
• Difficulty calculating and assigning complex bills with tax and discounts for both group and individual expenses.
• Difficulty tracking who has or hasn’t paid.

Low-fidelity wireframes were developed based on these findings and refined into high-fidelity prototypes. Multiple user testing sessions were conducted, with user feedback incorporated iteratively to improve flow, clarity, and visual hierarchy. Through these refinements, BillBro evolved into a solution that simplifies the process of calculating, assigning, and tracking shared expenses—ensuring smoother trips and less financial confusion for everyone.

BillBro’s visual direction focused on creating a friendly yet reliable aesthetic, reflecting the app’s goal of making financial management approachable.

Color Palette Iterations:

The color palette underwent several iterations—initially starting with more vibrant hues to evoke energy and social interaction.

However, after testing, these were refined into a calmer, modern palette dominated by soft blues and neutrals, representing trust, clarity, and ease of use. Accent colors were then added to highlight key actions (like adding bills or confirming payments) without overwhelming the interface.

Typography:

BillBro uses SF Pro, Apple’s default system font, ensuring high readability and a native iOS look and feel. The consistent use of SF Pro across screens contributes to a clean, cohesive visual hierarchy that supports usability and accessibility.

The result of the project is a fully built iOS app now available on the App Store, marking a complete design-to-product realization.

BillBro successfully delivers an experience that helps users simplify complex group expense management, making it easier to calculate, assign, and track bills transparently. The app has been praised for its intuitive layout, clear expense summaries, and visually lightweight design that makes even financial tasks feel approachable.

During testing and post-release feedback, users noted that BillBro:

• Reduced confusion in managing group expenses during trips.
• Decreased manual work by eliminating the need for spreadsheets and messages.
• Improved accountability by clearly tracking who has or hasn’t paid.

What began as a tool for group travel has now expanded into a flexible platform for both shared and individual expense management, highlighting BillBro’s potential to scale into broader financial contexts.

You can download BillBro on the App Store here.

Through this project, I learned the importance of:

• Understanding user behavior deeply to uncover practical, real-world pain points.
• Iterating based on user feedback to ensure the product solves the right problems effectively.
• Designing for clarity and trust in financial contexts, where even small interface details can affect user confidence.

BillBro taught me how thoughtful design can simplify complex social and financial interactions—making shared experiences smoother and more enjoyable.