Until that time arrives, only developers have access to Android M, and up until this week, they were running the same “tired old” build Developer Preview build that was released in late May. Thankfully, Google yesterday released Android M Developer Preview 2 which brings a wealth of updates to the operating system.
The changes center around three key areas: Android Platform, API, and issues pointed out by observant developers. Android Platform updates include modifications to permissions for external storage, Wi-Fi/Bluetooth location reporting, and contacts (just to name a few). API changes include updates to the Bluetooth Stylus API and the Media API.
Something that has unfortunately been removed from Developer Preview 2 is the Dark System Theme. Google introduced this feature with the first developer preview and it was well-received. According to some reports, the Dark System Theme likely wasn’t ready for prime time in these early test builds, and will likely find its way into the final release of Android M.
Google says that devices that already have the first developer preview installed (including the Nexus 5, Nexus 6, Nexus 9, and Nexus Player) can upgrade immediately to Android M Developer Preview 2 over-the-air (OTA). All other devices currently running the the first developer preview, such as these Xperia models from Sony, will receive OTA updates over the next few days.