This is an app for treasure hunters. There is a large collection of antique maps of Russia that you can overlay on top of a Google map. Also the app contains coin catalogs. Maps and catalogs can be bought with in-app purchases. I subcontracted a designer, backend developer, and Android developer to develop this app, leaving iOS development for myself. That’s not how I work nowadays, by the way. Nowadays, I only subcontract a designer and do all the coding myself.