iPhone Superheating post recent MineCraft update

Hi there, since the new update that went in and the realms came back online after being down yesterday it seems myself and my friends who play on my Realm (3 users) all have a problem with their iPhones / iPad getting superheated. Nothing has changed except the update - one phone even got so hot it triggered Apples shutdown and warning while the phone cooled down. It was too hot to touch on the back of the phone.

Is there a bug causing the phones to superheat?