The native prompts don't allow for app specific explanatory text to be presented. I haven't reviewed iOS guidelines, but Google provides guidance to inform users of why you're asking for permissions before you do it, and I would guess Apple would suggest the same as well. Pestering people for access once a day is probably not within the scope of the guidelines though.
Not true. iOS apps can specify explanatory text to be included in the native prompt. In fact they are required to do this, since at least two years ago.
The NSContactsUsageDescription string (in the Info.plist file) is the place to specify this.
https://developer.apple.com/library/archive/documentation/Ge...
There is no good reason for Apple to allow apps to mask permission requests with their own dialogs, it’s just a case of not bothering to fix this loophole.