Following with tradition, the latest version of Android version will be revealed during Google IO 2015.
While this information hasn't been officially disclosed by Google, The Verge reports that a session description for the conference briefly surfaced and specifically mentioned "Android M." The document referenced has since been removed from the Google IO website, but Android Police posted a screengrab of it.
Android 5.0, or Android Lollipop, was first known as "Android L" when it was announced at IO 2014. Despite Lollipop only making it to 10% of Android users, Google appears unplused and plans to discuss the newest Android variant.
Although the IO description is tight-lipped about the details, a few cryptic hints were dropped. The "Android at Work" session summary that revealed Android M's presence says the update "brings the power of Android to all kinds of workplaces." With Google constantly expanding into new territories, it sounds like Android M will focus on bringing Google's power to businesses.
Other session descriptions reveal Google has done work to improve notifications introduced in Lollipop as well as work to offer more robust voice controls, giving users new ways to interact with their Android devices by speech alone. We'll find out more about these new features and Android M in a few weeks' time.