Fps stands for - FRAME PER SECONDS
★First why fps decrease : phone temprature up and less memory avaible for run games .
Fps increasing depends in mostly at device storage space , and sometimes it's also issue of game optimization .
How to increase fps -
Follow this things and check one by one .
Update your software(such as system apps and system update)
Set game mode( in many phones available )
Increase refrest rate ( my recommendation 90 is well )
Enable DND[Do not disturb ]
Limit background process ( Available in developer options )
( ☝️Some setings is not available in every devices )
Final recommendation - game booster app also can work sometimes .
( Proof - It's all testest by me )
That's only proof i can give.
[ Video come soon at YouTube ]

alm1ghty
if you are talking about phone you can forget about fps lol
alm1ghty
if you are talking about phone you can forget about fps lol
Sertr
My phone lags after turning on game booster lol. I still drop quite a lot of fps in general but recently i started dropping even more severly. (Phone is pretty new so basically clean and empty)