These days, there are many strategy and first person shooter games available on mobile However, not even a single one is as good as the Gameloft's world famous "SNIPER FURY". Not only it is a first person shooter game, but it is also a very good strategy game. Players can make their own base and attack/defend the bases.
if you want ruby and gold, then you must sniper fury hack available here: http://www.sniperfuryhack.xyz/.
There is also another way tog et rubies beside using a sniper fury hack and that is going inside game store and buying in-app purchases.