Apple scans on each and every app submitted to App store. Our responsibility is to make sure app followed all App Store review guidelines and will get approved before dead line. But sometimes the guidelines are interpreted differently by different reviewers and frequently change over time.
Interestingly, I exposed to some common and "repetitive" rejections. Those I listed below and you are welcome to consider it as your checklist.
1. If the app contains any kind of bugs and crashes will surely rejected. Make sure app involved in testing and cleared test cases. Also involved various iPhone models & iOS version in the process.
2. Lacking of meta data is also leads to rejection. The key point is Apple expects behaviour of app should match with app description.
3. If the app submitted with demo features will be considered as incomplete. So make sure your app doesn't include keys like 'Beta', 'Demo' or 'Test'.
4. Even missing demo account of app could stop reviewing process and will be rejected.
5. The app configuration (.plist) file not specifying correct background functionality (audio control, background location, etc.) can be another reason for rejection.
6. If you use the Private API, then the App Store will reject your app (iOS app). Apple provides both private and public APIs, but only public APIs are allowed you to use, whereas private APIs are only used by Apple to prevent from misusing the user data.
7. Do not miss out iOS advertising identifier (IDFA) in case app has ads functionality. In case app doesn't have ads, skip IDFA. Otherwise app will be rejected for both cases.
These are the very common rejections that I have experienced till date. The list is never ending. So, comment down those rejection reasons that you might have faced and you think it is very common.