I’m not trying to discourage you and I didn't make this stuff up, just to get your business! This info came directly from the source: https://developer.apple.com/app-store/review/rejections/
Take a look at some of the challenges I’ve listed below and if you need any help sorting all of this out, connect with me TODAY!
Crashes and Bugs - You should submit your app for review only when it is complete and ready to be published. Make sure to thoroughly test your app on devices and fix all bugs before submitting.
Placeholder Content - Finalize all images and text in your app before sending it in for review. Apps that are still in progress and contain placeholder content are not ready to be distributed and cannot be approved.
Incomplete Information - Enter all of the details needed to review your app in the App Review Information section of iTunes Connect. If some features require signing in, provide a valid demo account username and password. If there are special configurations to set, include the specifics. If features require an environment that is hard to replicate or require specific hardware, be prepared to provide a demo video or the hardware. Also, please make sure your contact information is complete and up-to-date.
Inaccurate Descriptions - Your app description and screenshots should clearly and accurately convey your app's functionality. This helps users understand your app and makes for a positive App Store experience.
Misleading Users - Your app must perform as advertised and should not give users the impression the app is something it is not. If your app appears to promise certain features and functionalities, it needs to deliver.
Substandard User Interface - Apple places a high value on clean, refined, and user-friendly interfaces. Make sure your UI meets these requirements by planning your design carefully.
Advertisements - When submitting your app for review, you’ll be asked whether your app uses the Advertising Identifier (IDFA) to serve advertisements. If you indicate that your app uses the IDFA, but it does not have ad functionality or does not display ads properly, your app may be rejected. Make sure to test your app on an iOS device to verify that ads work correctly. Similarly, if you indicate that your app does not use the IDFA, but it does, your app will be put into the “Invalid Binary” status.
Web clippings, content aggregators, or a collections of links - Your app should be engaging and useful, and make the most of the features unique to iOS. Websites served in an iOS app, web content that is not formatted for iOS, and limited web interactions do not make a quality app.
Repeated Submission of Similar Apps -
Submitting several apps that are essentially the same ties up the App Review process and risks the rejection of your apps. Improve your review experience — and the experience of your future users — by thoughtfully combining your apps into one.
Not enough lasting value - If your app doesn’t offer much functionality or content, or only applies to a small niche market, it may not be approved. Before creating your app, take a look at the apps in your category on the App Store and consider how you can provide an even better user experience.