I have 2 same S4's, but one of them lags when I play a game. Why does this happen?

[AC Question]

I have 2 same S4's, but one of them lags when I play a game.

I have 2 Samsung S4's (SGH-I337). They have apps installed on them. I only have a few apps (FB, messenger, Instagram etc.) installed. They have the same data too. But when I play a game (same one), one of them lags, one doesn't... I checked the memory, still a lot available. And there aren't too many processes running either. I have no idea why? Please help...

 

[liu8651]

Re: I have 2 same S4's, but one of them lags when I play a game.

The models are GT-I9500 and SGH-I337. SGH-I337 is the one having the problem. They both have Android 5.0.1.