I've had this iPad app up and running for about 4 and a half years - I don't think I've broken even yet on the amount I paid an artist for the graphics for the app. I did the coding for it myself.
This service is pretty straightforward, and has users, but doesn't really cover the server costs. On my list of things to do is to switch it from PhantomJS to headless Chrome, and then to migrate the server.
https://itunes.apple.com/us/app/cat-game-aquarium/id56449037...
I've had this iPad app up and running for about 4 and a half years - I don't think I've broken even yet on the amount I paid an artist for the graphics for the app. I did the coding for it myself.
RobotBridge PDF Conversion as a service (API)
https://market.mashape.com/jefflinwood/robotbridge-pdf-conve...
This service is pretty straightforward, and has users, but doesn't really cover the server costs. On my list of things to do is to switch it from PhantomJS to headless Chrome, and then to migrate the server.