Don't worry, everything is fine.
I don't play with my Note, but if I stream Music, Navigation active and surf the Web at the same time, the temperature goes to 40°C
playing games is much more cpu work.
Enjoy your phone and relax
Every Device with a CPU goes warm. If this is a issue , so my TV, Laptop, PC and so on is broken
All devices have a aktiv or passiv cooling unit, just Mobile Phones don't have. 43°C is under this circumstances a good result.
Hope you understand my bad English and you know what I try to told you?
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