• Permissions - Now the user has control over the permissions each app may or may not have. Thus, when using this app you may encounter a message asking permission for such a thing.

• App Links - Now you can open links within certain apps without having to choose which browser you want to use, just select only once your preferred browser and voila!

• Battery -  Android devices smarter about managing power through a new feature called Doze. Android uses significant motion detection to learn if a device has been left unattended for a while. In this state, Android will exponentially back off background activity, trading off a little bit of app freshness for longer battery life. Consider how this may affect your app; for instance, if you’re building a chat app, you may want to make use of high priority messages to wake your app when the device is dozing.

The Android M release: advancing assistance and payments

• Now on tap - Now it's easier to get help with Now on tap - Whenever They need it, wherever They are on Their device. For example, if your friend texts you about dinner at a new restaurant, without leaving the app, you can ask Google Now for help. Using just that context, Google can find menus, reviews, help you book a table, navigate there, and deep link you into relevant apps. As a developer, you can implement App Indexing for Google search to let users discover and re-engage with your app through Now on tap.

Now on tap

• Android Pay & Fingerprint - The Google has built with Near Field Communications (NFC) in Gingerbread and Host Card Emulation in Kitkat to develop Android Pay. Android Pay will enable Android users to simply and securely use their Android phone to pay in stores or in thousands of Android Pay partner apps. With Android M, native fingerprint support enhances Android Pay by allowing users to confirm a purchase with their fingerprint. Moreover, fingerprint on Android M can be used to unlock devices and make purchases on Google Play. With new APIs in Android M, it’s easy for you to add fingerprint authorization to your app and have it work consistently across a range of devices and sensors. These are just a few highlights from the Android M Developer Preview that has anunciada today. The Android M preview already available for download.

• To download the Android M preview, simply access this link. 

(Remembering that can only test the Android M preview, who's Nexus line of devices user.)

Source: Android Developer