Hi guys! 
Recently I'm building a water robot(roBoat), I use a wireless port to sent him the way-points, with a nice antenna it will work around 400m. But just now I thought about mounting a GSM shield on that and use my cell phone text him to tell where to go. I guess it's feasible, but I didn't play with GSM before and now I wonder how to get the way-points from a message and, yea, convey them into programming? Maybe I should use another array to store the way-points from the message and replace the old ones I've already downloaded, hoho, that may work. If you have other inspiring ideas just drop comments below, I'll be glad to see them! 
Thanks in advance!
This robot maker: Tinker92