Same here. I was only in a brisk walk for 20 minutes, not jogging, and the overheating warning came on. It was 28°C at the time but still, I was not using the watch for calls or music controls etc at the time. Also, as has been mentioned elsewhere, the battery life is disappointing. I'm getting between 7-8 hours at most the last few days and having to charge from single figures to 90-100% twice a day. I think my device must be faulty as it's too bad to be true
Only solution I've found to overheating and battery drain is to turn of mobile data and almost everything I can, just leave bluetooth on, I know crazy right.... we buy the 4g version but it's unusable.