A question about the fix that worked for you: Did it involve wiping your iPad Air clean of all data and then restoring the data "from scratch" as opposed to from a previous backup from your iPad 3? In other words, did it mean that you basically just had to start over with the Air as a brand new device with no accumulated data from your previous usage of older devices?
I ask this because I have been very resistant to trying any kind of possible fix that would basically require me to start my iPad experience over from scratch. I had about 2 1/2 years of data accumulated in heavy usage on my iPad 2--including several gigs worth of documents I use constantly in my work, and naturally media, photos, etc., and reams of other data in various apps that are critical to my daily work and personal life--before getting iPad Air. The prospect of having to rebuild this collection of data by hand is really a nightmare scenario for me, and a cure that may be worse than the disease. (And if that is indeed the case, I don't consider it a true 100% "fix" because one of the Apple things that traditionally "just worked" was the ability to seamlessly transfer your experience/data on an older iOS device to a brand new one. If this kind of rebuilding from scratch is the only option Apple is leaving us with, it will certainly influence my decision on whether and when to buy new replacement iOS devices in the future. If I have to redo everything anyway, why not explore other alternatives?)
I'm certainly VERY hesitant to even risk the hassle and time commitment of trying this kind of rebuilding if it is not a 100% surefire solution. And I really have my doubts because in my case (as I have posted repetitiously), I have had the same problems on my iPhone 5 and iPad 2 since Day 1 of downloading iOS 7.