Google introduces Android M

“Today with the final Developer Preview update, we’re introducing the official Android 6.0 SDK and opening Google Play for publishing your apps that target the new API level 23 in Android Marshmallow,” Android product manager Jamal Eason said in a post on the Android Developers blog.

“The final Android 6.0 SDK is now available to download via the SDK Manager in Android Studio.”
Android Marshmallow is mostly geared toward improving user experience, but also adds new features.
One of the key changes is the control of app permissions. Users will be able to choose to grant permission for apps to run, meaning developers will be able to have their apps operate faster once a user gives the sign-off.