I can confirm having the timer issue on my iPad 4 too. It always happened since DP (don't remember pre-dp), usually in long games or seldomly and randomly in shorter ones. Sometimes I play a guildmate in iPad 2 vs iPad 4 friendlies, the iPad 2 suffers severe freezes quite often, so we can finish 2/3 of the games we start, no joke! My Android phone never has issues, really thinking of dropping the iPad (no love btw) and get another android just to play SE...
What I dislike is that Appstore reviews make us wait even further every update Wulven tries to push, and then the IOS app is even less stable than its Android or PC/Mac/Browser counterparts... Funny!