There is a good graal like game on ios,but it is more of a multiplayer game.It is free roam but it's free roam is like in gta 1 and gta 2-payback 2.It is free and it has an awesome multiplayer.You should try it.It has different game modes like kingpin,races,knockout races,capture the swag(case),deathmatch,team deathmatch,zone holding.