I am still on iOS 6 on my iPad Retina (3rd Gen. "The New iPad). It runs smoothly and I just stay off public WiFi and avoid doing security-critical stuff with it. Mainly, I use it for posting here and reddit, reading forums, playing music apps from Korg and Moog, and photography-related stuff. My battery still lasts longer than my GF's Air 2 lasts, even though my old iPad is like 3 years old now LOL. But there are some music apps and app updates I cannot use due to iOS 6 incompatibility. I avoided 7 and 8 due to lag issues. I read somewhere that 9 is supposed to run better on older devices. Will my iPad work as well as it now does if I upgrade? A little bit more lag might be OK but I've heard 8 makes this device basically unusable. Thoughts?