This just started happening (to me), and recently started...
When attacking a player (not a building), the game freezes (rival profile, to my base, clipboard and gunsights all dimmed out) but can click on top icons (gold, energy, etc) with normal action. Have to restart game to continue.
Occurring on 2 iOS devices (iPad mini 16gb 8.1.2 and ipad 3 64gb 8.1.2)