When an iOS app attempts to register for push notifications for the first time, the system pops up a permissions dialog asking the user for permission to receive push notifications. Is it possible to customize the text of this dialog, to explain why these permissions are being sought?
No, this is a system dialog which cannot be customized.
One workaround that I have seen involves an app bringing up its own custom dialog explaining why it needs a permission. Then immediately afterwards the app requests the permission, bringing up the system dialog.
This may be suitable for convincing a user to accept the permission request in order to gain access to a feature, or to reject the request with the knowledge that the feature will not be available.
Not possible, since you dont have any control on it whatsoever
No you cant change system in built message.because you dont have any control to it.
Recent versions of iOS do allow these permission dialogs to be customized.
Put your message in the NS*UsageDescription Info.plist key corresponding to the type of permission dialog you want to customize.
For example the NSCameraUsageDescription key controls what dialog text to display when requesting access to the user's camera.
来源：https://stackoverflow.com/questions/10963711/customizing-the-ios-permission-dialog-for-push-notifications