So I’ve always just milled my souls out with a combination of Valk, Necromancy, and more recently Pharos-Ra but a guildmate just bought a bunch of souls to help get some kingdoms up to five stars and became extremely irate when they noticed it would have been cheaper to do so on PC than on Android. That got me looking and there are actually quite a lot of price differences. These are PC screenshots with the mobile screenshots pasted in
So Souls, our starting point, actually changes benefits depending on which version you are in.
Gold on the other hand is all PC’s way.
But the part I find most disturbing is the real world currency difference. Chalice is the same in both versions incidentally.