I reboot also my galaxy a8 but

[Android Central Question]

It's the same my device is overheating...what can I do?

 

[B. Diddy]

Welcome to Android Central! More details would be helpful. When does it overheat? Do your battery stats show any app using an inordinate amount of battery? How's your cell signal? Charge up to 100%, then let it drain to 20-30% with normal usage, without charging in between. Then show us:

1. The main Settings>Battery screen.
2. The fullscreen battery graph screen (which shows Awake time and Cell Signal Strength).
3. The Screen category (to see total Screen On time).
4. The Cell Standby category, if present (to see Time Without Signal).


http://forums.androidcentral.com/ge...ide-how-post-screenshots-android-central.html
You might have to install a 3rd party battery monitor, like GSam Battery Monitor, to get the Cell Signal Strength graph.