Massive Lag on LG G3 metal gear solid peace walker

[theastralist]

Hey guys ,I'm New here and I don't know if this is the right place to post this but,I'm getting like 8 to 11 fps while playing metal gear solid peace walker in my lg g3 ( 2gb RAM variant) . I tried tinkering with the settings but it works smooth at 20 fps when the camera is looking at the sky or at a distance. When there are elements like soldiers it drops to 8 fps . can anyone help me out ? Settings or otherwise ?