I remember when the iPad came out I was incredibly excited. This was surely perfect for RTS games!

There was Command & Conquer: Red Alert Mobile, then....

The only other one I remember was an actually really good StarCraft clone by Gameloft (I forget the name).

I always thought mobile would be great for RTS and then it just wasn't. Though when I think about it, the keyboard is pretty important and that kind of fast control is really difficult on a touchscreen, so maybe that explains the lack of 'classic' RTS games on touch devices.