Iphone 4S hot battery

[kman9845]

Does anyone know why the iPhone would be hot while the battery is charging? Doesn't happen all the time but I'd say 75% of the time.

 

[Skull One]

The chemical process of charging produces heat. It usually only happens during Stage 1 charging or if you are using the device at the same time especially with a high brightness setting. Also the ambient temperature, where you are charging, can be a contributing factor.


So it is very normal.