Web and Phone App: Strava

Strava lets you track your rides and runs via your iPhone, Android or dedicated GPS device and helps you analyze and quantify your performance. The Strava Labs: Global Heatmap also enables you to see the most popular cycling routes used by Strava riders in your city. Many of these are recommended transport routes.

Links:
> Strava web app
> Strava mobile apps
> Strava Labs: Global Heatmap