User blog comment:Cbird2796/Update - 2.9 Patch/@comment-69.249.70.255-20130529212345/@comment-4632427-20130530013946

In my case, I think it's probably just memory bloat combined with the fact that I'm using an old-ish iPhone 4. I'd guess folks with better hardware probably don't have my problem. Still annoying when it makes my phone unusable for ~5 minutes at a time, though.