[JonnyaiR]

They have two different privacy solutions implemented in Android 6 (marshmallow): The first one is comparable to iOS' model - the app must ask for permission on first access. If the user denies said access, the app gets this information.

Ghe second solution is aimed at apps designed for older Android versions, if the user denies access, the app gets empty data back (e.g. Empty contact lists, no GPS satellite etc).

An app designed for Android 6 should handle negative feedback (disable functions, show a warning/explanation or something else), it shouldn't break. If you don't want to handle this, design for Android <6 and let the system take care of it. But it should be a difference between permission not granted and no data available, apps should handle these issues differently. If I were to deny my navigation app access to my location, it should ask me to revoke this decision and not warn me about not finding GPS satellites (which would make me run around with my phone hold up in the air hoping to get a GPS fix).

[nitrogen]

If I were to deny my navigation app access to my location, it should ask me to revoke this decision and not warn me about not finding GPS satellites (which would make me run around with my phone hold up in the air hoping to get a GPS fix).

That kind of notification should be done by the permission system itself, perhaps as an icon in the status bar.