The Xbox One controller is one of the most popular gaming controllers out there, especially since the latest revision finally added Bluetooth support for easy pairing with PCs and mobile devices. However, using the controller to play games on an Android phone wasn’t a great experience until now, especially because of button mapping issues when connecting the controller via Bluetooth.
Two years ago, Android users warned Google of the lack of controller mapping for the Xbox One controller. The company has finally fixed the issue in Android Pie, which was officially released earlier this month (via XDA-Developers). If you have one of the few Android phones that has already received Android Pie, the Xbox One controller should now work as expected when you connect it via Bluetooth (you can also connect the controller via USB, but a wireless connection is preferable for many).
You may not see many people playing smartphone games with a controller, but this may well change soon now that you can play PUBG, Fortnite and PC/console games on your phone. Unfortunately, you still can't use an Xbox One controller with an iPhone or iPad since these devices only work with "Made for iPhone" controllers that have been certified by Apple.