FitFunds is a mobile app that invests your money every time you skip a workout. As people who are passionate about fitness and interested in investing, we imagined an intersection between both worlds. We realized that if skipping the gym had a financial consequence, we’d be motivated to stay consistent. That’s when we thought: what if missed workouts turned into investments?
Users commit to a weekly workout goal, and if they don’t meet that goal, a self-selected amount of money is automatically invested into the stock market via the Alpaca API. This system turns skipped workouts into long-term financial assets, combining fitness accountability with passive wealth generation. At its core, FitFunds transforms inconsistency into investment.
How It works: Frontend (React Native): Users interact with the app to register/log in, set fitness goals and investment amounts, enter API keys from Alpaca, log workouts with an “I'm at the gym” button that triggers GPS validation, and view progress and portfolio performance.
Backend (Python + Flask): Exposes secure API endpoints to handle workout logging and location validation, store and process user-defined goals and investment parameters, and authenticate and interact with Alpaca using user-supplied API keys.
Investment logic: At the end of each week, the system checks how many workouts were logged. If the goal is not met, the system calculates how many workouts were missed, multiplies that by the pledged dollar amount, and places a market order for that amount into the VOO ETF (S&P 500 tracker) using the Alpaca API
Profit calculation: The backend retrieves all filled buy orders for VOO and the current market value of the user’s VOO holdings. It then compares the total cost basis to the current value to determine the total amount earned.
The main difficulties we faced during this project were: API integration: understanding Alpaca’s paper trading system and safely handling API keys was a challenge, especially without OAuth access. Behavior verification: validating gym check-ins with GPS was tricky, and we debated how much verification was enough for a functional MVP. Balancing simplicity and value: We had to be intentional about what features to include. The challenge was creating something powerful, yet simple enough to launch and scale.
We’re proud of building a functional MVP that connects fitness behavior with real-time investing. We successfully integrated Alpaca’s paper trading API, created a GPS-based workout check-in system, and designed an experience that’s simple, scalable, and beginner-friendly. Most of all, we turned a common personal struggle into a meaningful financial opportunity.
Building FitFunds taught us much about behavioral economics and how simple incentives can be extremely powerful. We learned everything that goes into integrating third-party APIs securely, especially in a fintech context, and how to manage time-triggered backend logic tied to real-world events. We also explored the fine line between accountability and user friction: how to motivate behavior without overwhelming users.
Future improvements & scalability: Enhanced workout tracking with step counting, route tracking, biometric data from wearables (heart rate, calorie burn, etc,) and Integration with Apple Health, Google Fit, and Fitbit APIs. Expanded investment options include predefined investment profiles (conservative, balanced, aggressive), custom portfolios, and thematic investing. User experience enhancements with OAuth integration with Alpaca for secure account linking; social features like team challenges, shared goals, and group accountability; and smart notifications and reminders. Monetization Potential with premium features (e.g., investment customization, analytics), affiliate partnerships with fitness brands or financial services
Log in or sign up for Devpost to join the conversation.