I tried the same list of games I used while streaming to my TV. Since I don't own a tablet, it's a little hard for me to imagine wanting to play a PC game on my phone using a Steam controller, but I did give it a shot and it works really well. Again, it's hard to say if this issue has to do with the app, the Apple TV box, or the controller itself, but something still needs some work. With my physical Steam Link box, I don't recall ever having issues pairing a wireless controller to it. So I'd have to try again, sometimes repeatedly. Usually it spotted the controller right away, but occasionally it took several tries, and once or twice after it had detected the controller, I'd answer the prompt to pair the controller only to find it hadn't paired.

I had issues pairing my Steam controller with the Apple TV box a number of times this week. I unplugged my Ethernet cable and tried the same games over my 5GHz wi-fi connection, and not unexpectedly the performance wasn't quite as smooth, though everything I tried was still highly playable. I can imagine it would be frustrating in a competitive match. These little skips didn't make the game unplayable, but it's neither as smooth as it is on my PC or on the Steam Link. Playing Rocket League online on my TV, I had occasional dropped frames or stutters now and then, though it's hard to say where the problem lies-with my connection, with the Steam beta I had to opt into for these tests, with the app itself, or the Apple TV box. A network testing option will tell you if your system will be able to handle running the Steam Link or if you'll need to make some adjustments in the options menu. There are settings in the app for streaming quality: you can choose from Fast, Balanced, or Beautiful (I swapped between Balanced and Beautiful a few times, without noticing any change in visual or performance quality), you can set bandwidth limits from 3 MBit/s to unlimited, and you can limit the resolution, if native res is too taxing for your connection.

Android steam link controller