It works out speed, averages and calories burnt in real time GPRS. So now you can motivate yourself to beat your first time, and lose weight!
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My weight has gone up from 75kg to 98kg, I have 3 blockages in my heart, the worst is 60%, and i thought my fitness level was very poor, even though I run regular, I couldn't lose weight, because i was having 2 bottles of beer each night. that would be an extra 1200 calories, not forgetting the nights out with SMS....every 3 months or so, that would be 3600 calories in one booze up.
Anyway, I have stopped the beer and now hope to see some action on the scales, over the next month.
You can share your efforts live or keep them private, enjoy!
My time to beat is 1hr 4 minutes for 8.4km. 3 years ago, I would have done 8 km in 48 minutes, weighing 80kg so the extra 15kg slows me down a lot, also reduced oxygen intake now...Don't be concerned if I drop dead, it will be doing something i enjoy! (sex and pain)
Only joking guys 
The application is a networking community so you can challenge each other in real time or just make friends for the occasion.
Must be the DrinkingVinegar i was drinking, as i haven't run the last 10 days, and i lost more weight than i did running 1.5 kg in 10 days, though i have been to busy to run, with a lot of walking around.