I need to be able to do these few things:
- Run my app on phone startup
- Keep it running in the background all the time
- No UI is needed – this is a statistics app so it will gather all the data it needs and the user should not be bothered with anything.
Are these things possible?
Not really. Setting aside jailbreaking and the universe of things that aren’t Apple-approved, running in the background full-time is explicitly banned on iOS. Similarly, you can’t sell an app on the App Store that doesn’t have a user interface, and you can’t set apps to run on start up.