Game crashing

Both on 1914 supremacy and call of war mobile,the big world maps crashes the game.On 1914 it gives players a warning that 500 player map will crash and I've experienced the 100 player map has a lagging delay at times which makes playing frustrating even the COW 50 player map lags but does not crash.On COW 1939 Historical World War 30 player map,it has recently became unbearable to play,after few minutes the game freezes and then throw me out to my phone home screen, therefore I have decided to abandon the game and half of the African continent I have captured.So I have to stick to 22 player map Clash of nations