use cheat engine to increase speed (the grind is still kinda long)
On Android, there's no way to stop the grind unless you root. Also, all mods that mess with speed on Android ruins the sound, as in you can't hear much other than bits and pieces of the music. Game killer is literally a game killer. (Edit: the mods that mess with speed can also actually slow your game down, this happens pretty frequently so it's not worth it.)