Marshmallow gives users more ways to manage their app permissions. Before, Android users were only able to grant or deny all permissions at once before installing the app. With Android 6.0, users get a notification every time an app wants to access a certain part of their device—like the camera, microphone, or location services.
Android users will also be able to see and change the level of access they’ve granted for each app, under Settings > Apps > Gear icon > App permissions.
Forcing apps to ask for specific permission and allowing users to control these permissions anytime has been incorporated in iOS for quite some time.