Does anyone know a good app to tell me how far I've run while running

What mobile device do you have, if you have an iPhone then you have an app called health, it tracks how much you've walk and ran

Oh cool thanks.
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Ok so how do I make it tell me how far I've walked. All I can find is how to manually put in this information.

On the dashboard of the app it should just tell you in steps, walking and running distance and flight climbed

I recommend Nike+ Running, it's the best imo.

I am 99% sure that on Spotify it has a running section that tracks your running stuff while you're listening to music.