Running

I'm going to give this Run Keeper Pro app a go too. Would be nice to keep a log of my runs and to check progress. Going to test it out tonight in fact!

I started using this this week, i found the 5 minute updates on pace really useful and the the 3 runs i used it on were faster than anything I'd done previously, I was delighted. However I was a bit puzzled how my speed could vary so much when I felt it was constant and the total length was always less than the distance I planned on Goolemaps, which was a bit of a blow as I'm training for an April Marathon.
Last night 6 miles into an 8 mile run my pace dropped by a minute per mile, I nearly gave my self a heart attack to bring it back to my target, I've never run so fast over a prolonged distance.
When i got home i checked the route and the GPS signal had obviously dropped out when i was doing a loop of a park, it plotted 3 points rather than the loop, shortened the section of my run from a circle to a triangle and made my pace slower accordingly.

Back to the drawing board. Looking for a way to check pace during a run that is relaible and ideally cheap.