Coin Counter

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Inspiration

Counting coins is always a hassle. Whether you're a tourist who travels to other countries and is unfamiliar with the currency, a server who needs to count all of their change before clocking out, or someone who has a giant bag of coins that needs to be brought to the bank, the task of counting coins won't be something you're looking forward to.

What it does

The Coin Counter mobile app solves this problem by allowing users to take an image of their coins and having the app count their change for them! The app will display the amount of change they have for each coin and then give a total amount at the bottom.

How we built it

We used the React Native framework and its Expo component for the camera functionality. We also trained a YOLOv11 model to detect and classify coins. Finally, we set up a back-end server using Flask that ran the model and connected to the front end.

Challenges we ran into

We had some trouble connecting the React Native framework to the model, and there were some issues with where the images were being saved (since they needed to be saved on the mobile device). We also had a lot of bugs when it came to establishing a connection between the app and the backend server.

Accomplishments that we're proud of

We successfully connected the model to the front end, allowing the user to use the application without issues. We also fixed a lot of network connection-related bugs which helped us learn a lot more about the backend.

What we learned

We learned about the camera tools React Native offers and how to implement them in a mobile application. We also learned the importance of using a well-trained model and how much training a model can need, as using a model that is not sufficiently trained leads to poor results. Finally, we learned how to implement YOLOv11 into a mobile app and connect it to a React Native app using Flask.