This is the current game keeping me awake at nights
Bought the ios version for £2.99 over Christmas.
Its a turn based squad combat game with a campaign, so you can carry your characters over from mission to mission.
There are masses of campaigns and you can download new ones for free and it looks like you can make your own somewhere as well.
You got the usual mix of troops from fantasy land, and come with standard weaponry, HPs and so on.
Graphics are pretty basic.
Oh, just found out you can download it free on a PC or MAC
http://www.wesnoth.org/