If you're serious about running or cycling then you should be serious about Strava. As smartphone fitness tools go it's one of the best, allowing you to track your performance, set goals and see daily progress updates.
There are leaderboards and challenges to give it a competitive edge and if you're ever not sure where to run or cycle you can find user created routes on the app, or share your own. All of that comes free of charge, while a premium version adds even more tools.
Listed for app of the year at the TechRadar Phone Awards.