Sent by Cent

Inspiration

Managing spare change and making an impact can be difficult in our fast-paced world. We wanted to create an effortless way for people to round up their everyday purchases and donate the spare change to meaningful causes. Inspired by micro-donations and automated savings, we built Sent by Cent to make giving back as easy as spending.

What It Does

Sent by Cent helps users:

Automatically round up transactions and save the spare change.
Track their saved amount in a dynamic UI bubble.
Donate their saved spare change to charities directly from the app.
Manage linked accounts and view transaction details.
Track total donations made over time in the profile section.

With a clean and simple interface, users can effortlessly save and donate, making a difference with their everyday purchases.

How We Built It

Frontend: Built using SwiftUI for a smooth, interactive, and visually appealing user experience.
Backend: Integrated with the Nessie API for real transaction data and user account management.
State Management: Used @State, @Binding, @ObservedObject, and NotificationCenter to ensure real-time UI updates.
Global Variables: Implemented a singleton design pattern for tracking user data, transactions, and donations.
Navigation: Utilized NavigationStack and TabView for seamless movement between screens.
Data Handling: Worked with async API calls to fetch and process transactions efficiently.
Git Branching: Managed development with feature branches to avoid merge conflicts and improve collaboration.

Challenges We Ran Into

Xcode issues: We encountered several build errors and SwiftUI preview crashes, making debugging difficult.
State management: Ensuring real-time updates for donation amounts and transaction data without requiring a logout/login.
Nessie API limitations: The API sometimes failed to return transactions, requiring us to implement error handling and fallback data.
Git branching conflicts: Merging changes across multiple branches led to conflicts in UI updates and API calls, requiring careful merge resolution.
Syncing global variables: Keeping saved amount and total donations updated across multiple views without lag or inconsistencies.
Ensuring instant UI updates: The donation bubble and profile donation count initially required a logout to update. We solved this with NotificationCenter updates.

After several iterations, we overcame these issues with efficient data flow, improved state management, and a structured Git workflow.

Accomplishments That We're Proud Of

Successfully integrated real transaction data and automated savings calculations.
Built a dynamic UI bubble that updates with available donation funds.
Implemented a seamless donation system that instantly reflects changes across the app.
Designed an intuitive user experience for tracking donations and managing accounts.
Overcame state management challenges and ensured smooth, real-time updates.
Successfully resolved Git branching conflicts and maintained clean project structure.

Seeing everything work flawlessly in real-time was a major accomplishment.

What We Learned

How to efficiently manage global state across multiple views.
The power of NotificationCenter for triggering UI updates instantly.
Best practices for handling asynchronous API calls and data persistence.
How to structure a SwiftUI app with navigation, lists, and forms.
Debugging strategies for Xcode build errors, API failures, and Git conflicts.
Importance of proper Git branching and merging strategies to avoid losing progress.

This project deepened our understanding of SwiftUI, API handling, Git management, and app architecture.

What’s Next for Sent by Cent?

Expanding charity options – Allow users to explore and select from a wider range of charities.
Automated bank linking – Integrate with real financial APIs for live transaction rounding.
Analytics Dashboard – Show insights on donation trends and impact over time.
Recurring Donations – Enable users to set up monthly giving plans.
Community Features – Add a leaderboard to see who’s making the biggest impact.