Google has finally released its second update to the Android M developer preview, which makes this the third and final release of Android M before Marshmallow is rolled out to the wider public.
This third release has been billed as “near final,” and the official Android developers blog implies that changes from the second developer preview are pretty minimal. Many end users who are currently running the second version will certainly hope for a slew of bug fixes, though, including a wakelock bug on the Nexus 6 that prevents the devices from fully falling asleep sometimes, resulting in quite a bit of battery drain.
If you are running the second developer preview, you will receive an automatic OTA update over the next few days. For everyone else, you can download and flash the appropriate factory image from the Android Developer page, linked below.
This third release is available for the Google Nexus 5 by LG, Nexus 6 by Motorola, Nexus 9 by HTC, and Nexus Player by ASUS.[Android Developers]