Well it happens in the battle screen the worst it just freezes everything and a few to a lot of seconds later everything jumps to the current location.
When it sticks it also happens in the battle screen, it just stops and nothing happens till I refresh.
Both can throw the "an error has occurred" message, but I was getting those in the city as well I would get the blue circle and it would hang for a bit then the message would pop up. It said that it logged the error.