Did my "long run" today = 5 miles. So I usually run with my Gamin, but lately I've been running with my iphone and the "map my run" app (well actually it map my ride but it does the same thing!). The GPS on my phone shows me running longer--I've noticed this since I KNOW the distances of my various routes. Today for the 5 miles (per Garmin) my iphone GPS had me at 5.3 Makes a big difference in my overall pace. I'm planning to stick with my Garmin reading as I have always used that for distance and pace. Just wondering if anyone else has experienced this. I know GPS can vary.