For me, the problem is not with the iPad, at least not my iPad 3, although I have experienced for years the lag between clicking the keys and the characters appearing on my iPad screen in the Pages iOS app, currently ver 2.6.1 on iOS 9.3.1 (and with iOS 7 and 8 and prior versions of the Pages app), like everyone else who has reported the frustrating, incredibly bad lag. No amount of memory clearing and reboots solve the problem for longer than a few minutes, if at all. The solution? Don't use the Pages app. The Pages app is faulty. When I use the MS Word iOS app, ver 1.2, my keystrokes appear instantly on the iPad 3 screen, without any delay. After using Pages, using Word is like witnessing magic. All the frustrations fade away. The problem isn't the hardware or even iOS 7, 8 or 9. It's not your iPad or keyboard or the Bluetooth connection. It's the Pages app, even the latest version (and virtually every prior version). I don't have a dog in the hunt between MS, Apple, or any other tech company. Other word processing apps may work just as well as MS Word on an iPad 3 with iOS 9. I'm just telling you how to solve your key lag problem without spending a dime. Word. (all puns intended)
Keywords: lag, keystroke, delay, characters, screen, iPad, keyboard, typing, iOS Pages app, MS Word, hitting keys, time, seconds, slow, crawl, trail, limp, hobble, inch, plod, hang, wait, showstopper, hold-up, make coffee, watch grass grow or paint dry or water boil, die, eternity,