During registration with a Facebook/Google account the app checks whether there is a Facebook/Google account which can be used to register/ log into mobile-pocket. By activating your location on your device you can activate the "route" feature of the storefinder or receive location based notifications.
Granting permission to access Pictures/Media/Files allows you to upload pictures that you have stored on your smartphone to the app to use them as card pictures. With the phone camera you can scan the barcodes and take fotos of your cards.
The device-ID is needed to create a distinct user-number for the coupons account.