I have a XT910 since October 2013 and my Twitter app (official client) had always run smooth. Since, like, March of 2014 (5, 6 updates maybe?), the keyboard runs EXTREMELY slow when typing, and i've noticed this only happens on the official Twitter app. I had tried three keyboards, the stock one, Swype and Emoji 7 i think. With the three keyboards i had the same problem.
What I did was uninstalling Twitter, and downloading Tweedle, the best client i had found ATM. The thing is that this app has less options than Twitter and I really need to use it nice.
So I'll wait until Twitter fixes this problem (on the Twitter critics on Google Play, a lot of people had commented the same problem).
Meanwhile I hope there is a fix for this.
Had already factory reset twice, installed CM11, now im currently in stock JB again, but no fixes. I hope you can help me.
Sorry for my bad english