Doe's this app work and how spot on wood it be .its called urban biker .I got it yesterday and it has 5 stars from all the reviews. it worked really good yesterday my 142f hit 1run 53.6kmh 2run 56.8 .to day I put the app on and went out in my ten minute ride some where I hit 61 .3kmh that's 38mph I did try on flat road's just didn't seem that fast to me is the app not right or must it be true because of gps ??? here's a pic of app and the bike .its got a 54t on a 20inc wheel with a single chain gear box but rebuilt the in Side New shaft's one tooth biger sprocket and new hd chain in Side . I just didn't expect that speed.lol