Users can download the official ROM from Google Server itself.
Android cautions this version should only be used by developers and isn't intended for daily use. Check out the documentation on background execution limits to get more details.
Battery life is of prime concern to not only the users but also to the developers.
Picture in Picture (PiP) support is another big feature in Android O, coming years after third-party apps allowed you to do the same. You can even set and enable background colours for different sets of notifications. This is similar to the ones seen from the iOS, where numbers or texts in a balloon appear when there is an update from a particular app. For now, no betas or OTA images are available, which means users will have to flash the developer preview onto their devices. Developers have the ability to set adaptive icons which can change depending on the device.
Since a year ago, Google has been gung-ho about developer feedback, which is why it launched N Preview early. Android will allow for new "notification channels", which from Google's somewhat-vague description sound like a way for developers to roll up various types of notifications into a bundle a user can browse. Android O is trying to change this with 'notification channels'. It's the kind thing we'll need to see in action to judge, but it could potentially help to simplify a messy notification window. These changes are projected to enhance the feel of the platform and would also harvest on the powerful processor those most high-end devices come packed with.
Wireless audio, till now has not really been a breeze on smartphones, but now Android O supports high-quality Bluetooth audio codecs such as LDAC codec, which will give audio a boost.
Google has given its mobile search capabilities an overhaul, introducing new tappable shortcuts to surface information on selected topics much more quickly.
There's only one wallpaper now available from the developer preview, but it's a particulalry stunning shot which looks to have been taken by the ISS - though we're not 100% on that. "The company in its blog said that it is "focused on building a more reliable, predictable model for "arrow" and "tab" navigation" for users". As displays improve with newer phones and tablets, your apps will be able to take full advantage of all the colors and their subtleties.