Speaking of Android and its derivatives prior to the upcoming Marshmallow release (version 6), the permission model was based on all-or-nothing approach ("all"

Speaking of Android and its derivatives prior to the upcoming Marshmallow release (version 6), the permission model was based on all-or-nothing approach ("all" accept all permissions and STFU; "nothing" meaning not installing an app). There's a huge difference between informing user at install-time about all permissions an application requires and (not) knowing when they're used in run-time. In the Android world of cca hundred permissions and this all-or-nothing permission model, overall UX has suffered and caused tension between users and developers. As the latter keep adding features to their apps, sometimes requiring new permissions, some (aware and tech-savvier?) users will not feel comfortable about and even decide to uninstall the app just like some Spotify Android users already have. In this regard I've had a good experience with Privacy Guard feature on CyanogenMod 11 (based of Android 4.4 KitKat) and later. It allows you to control each app's access to a permission - allowed, ignored (disallowed), or "always ask". The last one triggers a popup whenever an app X wants to user permission Y (e.g. "Skype wants to modify your contacts" - wait what?!) where you can allow or ignorile it, and also set it as a future default to prevent being nagged with the popup. Although I personally very much like the option to opt-in or opt-out, I understand that even Privacy Guard UX is not for everyone. Luckily, you can choose if you need Privacy Guard and activate it per app, or have it automatically activated for every newly installed app with the "always ask" option for each permission.