I am working on iOS education app ,to use this app user should enter activation key for that user should contact company custom care then only user can proceed,if i upload this ios app should they accept or reject,what is the best way to build this type of requirement i have seen some links
Your app would most likely be rejected, since it violates section 3.1.4 of the App Store Review Guidelines:
3.1.4 Content Codes: Apps may not use their own mechanisms to unlock content or functionality, such as license keys, augmented reality markers, QR codes, etc.