The Android version of Trials Frontier is out now on Google Play, joining the iOS version that launched last month. Back then, Ubisoft claimed 6 million downloads within the first few weeks, making it their most successful mobile game ever.
Be warned, though: Trials Frontier seems indated with many of the the classic free-to-play pitfalls, putting up roadblocks for your playing that either requires paying or waiting a set amount of time to get around. In other words, you'll likely need to be the patient sort to get the most of the game - or get your wallet out.