Sport Watches

I want to use my itouch as one of the garmin watches with gps for runners but I have yet to find an application that that will let me do that, is there such a thing, will one come out soon or am I just asking for too much, and what would be the closest and best application for running, all suggestions are welcomed thanks!!!!

I don’t actually know if it would be made specifically for running, but that’s what I want one for. It seems like one should be available. Maybe a Garmin or something?
Thanks