So that the meat is tender I’m letting the meat simmer for 4 hours. I put ingredients like onion, ginger, mushrooms during that period. But potatoes I only put them near the end. I also sometimes add apples or pears for some sweet ingredients. Would it be best to put the apple at the same time as the potatoes or is ok to put them before?
I think it depends on how mushy you want them to be - you could add them with the mushrooms if you don’t mind them cooking down, but if you want them firmer you might adjust.
That said, I’m no authority on how to cook curry and don’t have any sense of the “right” way to approach this according to a particular food culture.