Is submitting an iOS app to the App Store free?

Rationale

There is a need to develop an app and test it, in my case, once upon a time, I did a project app for a school and the product owner wanted to test it, she asked me, how can I download it?

Answer:

No 😅, the reality is that if you want to use the app somewhere else, you are going to have to install it manually using XCode, unless you have a license for TestFlight so you can do some Beta Testing or you have the license to upload it to the App Store which is around $100.

So, the best way to test locally an app is to install it manually through XCode.