I think the heat problem come when the phone release at first, and hard to fix.
You must be can imagine when a machine work, they will produce heat. How if that machine is powerful, and the machine case is thin, of course that machine will make the case hot. That's the case of SGS4 i9500 imo.
So if samsung (or we ?) want to fixed it, they'll have to shutdown few core when the core is really not needed. But if the phone is used to play heavy duty game, all core will be needed and the phone will be heated by the core.
Samsung Galaxy S4 GT-I9500
Arrow Rom v.11.0.0 (Modem : DXUEMJ5) ~ Adam Kernel ~ ComaDose v2.1 with CrossBreeder V.7.2.13
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