Glance App
In February 2018, I led a winning team of four at a two-day Hackathon where we created an app to allow users to create intelligent location-based notifications, such as showing you your shopping list when you walk into a supermarket, or notifying you about student discount that is available in the shop that you're currently in.
Using Android Studio and various Google APIs, we were able to create an app that achieved this. We created a location-checking service that periodically checks the user's location to see if there are any notifications for them.