Samsung glaxy a9 pro have 8 gb of ram its mean you dont have to worry its speed is too good its battery is 4000mah u can upgrade its battery with a9 battery which is 5000mah I have use this smartphone on heavy load of internet play online games like clash of clans and candycrush etc but its battery never get down from 50% I have buy my sell about 9 months ago in pakistan I wnt to saudia and I am still using it but it will avoid warranty when you change sims in other country its recommendfor havy users only