Overheating has been an issue with Galaxy S7 and some earlier models. The heating has been to the degree that the device seem to hot to even hold. This is more so when you start to Enter VR World.
At the top of the list is the screen display compared to earlier models, multitasking applications and extended web browser on the internet.
Although you may find many suggestion and MOD kits to try an keep you device cool, it is best to follow some simple guidelines when using your mobile device for 360 VR. These may not work in all cases. Samsung states: "this is normal and should not affect the mobile devices's lifespan or performance"(pg. 11).
Items that MIGHT help:
- close all background applications
- set the brightness to low end, oculus will set it's own brightness when activated(default 70&) got to setting and reduce
- reduce continuous view and play time
- change adaptive display mode
- if connected to alternate power, turn off fast charging
- temperature should try to remain under 39 degrees Celsius