I'm running Public Beta 5 currently on my iPhone and iPad mini 4 and it FLIES. There's hardly any lag and it feels smooth and looks great too. This is what I thought iOS 9 was going to be like, but ended up being the opposite. Apple's very own marketing material made it sound like it was supposed to focus on bug fixes and enhancing performance. In my opinion, iOS 9 was even glitchier than iOS 8 was and the performance was CRAP. Even though they finally smoothed out the performance for iOS 9.3, but for some reason while doing that, they brought down the performance of the games that used to have 0 lag whatsoever. Even with the performance boost that 9.3 got, iOS 10 still beats it hands down. Then, when 9.3.2 came out, the auto-brightness brought even more lag to the table by rendering games barely playable if the lighting changed for whatever reason. This actually happened to me more than you would think. I would be outside playing a game, and if the sun went behind a cloud, or someone walked by causing a change in the lighting conditions, my games would stutter like crazy. iOS 10 fixed this for me and auto-brightness no longer affects games. So far, iOS 10 is shaping to be the breath of fresh air that we needed after the performance disaster of iOS 9. I really don't understand why iOS 9 was such an issue for them to get it working properly. That being said, there are still some things that need fixing in iOS 10, but it's already miles ahead of the very best version of iOS 9. I may even start liking Apple again. I was starting to wonder about their competence.