App developers

I assume you’ve seen this document, but if not check it against your App’s code -> https://developer.apple.com/app-store/review/guidelines/#privacy

In particular I would make sure you’re app is compliant with the required privacy policy guide (in the “legal” chapter). But also check some of the “design” sections. For a calendar, it may be that an App itself is not something Apple feels meets appropriate design criteria since their are subscription astrology calendars that are available and compatible with iOS calendar and 3rd party iOS calendar apps (those are available outside of the App Store as regular subscription calendars).

”4.2 Minimum Functionality

Your app should include features, content, and UI that elevate it beyond a repackaged website. If your app is not particularly useful, unique, or “app-like,” it doesn’t belong on the App Store. If your App doesn’t provide some sort of lasting entertainment value, it may not be accepted. Apps that are simply a song or movie should be submitted to the iTunes Store. Apps that are simply a book or game guide should be submitted to the Apple Books Store.

• 4.2.1 Apps using ARKit should provide rich and integrated augmented reality experiences; merely dropping a model into an AR view or replaying animation is not enough.
• 4.2.2 Other than catalogs, apps shouldn’t primarily be marketing materials, advertisements, web clippings, content aggregators, or a collection of links.“

As far as hiring a developer or software engineer, that’s the same as hiring any contractor. Ask for references, check them out online as much as possible, ask for examples of their work, contact some of their past customers if they list them in a web site, LinkedIn or somewhere. Just as with any contractor for anything, there are good ones and bad ones. It’s always a challenge when contracting with someone or some company, but good developers should be transparent about their experience, and proud to show examples of their work. I would also add, like many things, the really good ones will inevitably also not be the cheap ones.

This is a discussion which would better be supported in the App Developer Forum --> https://discussions.apple.com/community/developer_forums

I have asked the forum hosts to move this there, where you'll get better response from other's who develop apps.

I think you’re misinterpreting the App Stores response to your submission. There are numerous astrology apps in the App Store, so the issue is not astrology itself. So I suspect your app was rejected for some other reason - a violation of required privacy restrictions, a disallowed use of user data or some such issue with your code. But you will need to contact the App Store submission support through the developers support to find out what issue they had with your code.

Write a different app.

In the early days of the App Store, when Steve Jobs was still in charge, Apple was a little more straightforward. The App Review guidelines said, and I quote:

"We have over 250,000 apps in the App Store. We don't need any more Fart apps. If your app doesn't do something useful or provide some form of lasting entertainment, it may not be accepted."

That was just one of a number of "straight taking" bullet points.

Today, there are more than two million apps in Apple's App Store. So, whatever problems inspired Apple to write the above note are now ten times worse. Apple doesn't use this kind of colourful language anymore, but the core message hasn't changed. Your app has to be something that Apple considers of value to its users.

I want to repeat this point for emphasis, because I've said it many times and I know exactly what you are thinking right now. Your app has to be something that Apple considers of value to Apple's users. They are Apple's users, not yours.

Discuss it with Apple. You are not addressing Apple here. This is a user to user support forum and Apple does not participate here.