College Entrepreneur Creates App to Sync Music With Running Speed Michigan State University students created TempoRun, an app that helps users run at their ideal pace by categorizing the music in their libraries from walking to 10 sprinting.

Runners of any ability can relate to the feeling Josh Leider had during a summer workout last year. "'Lose Yourself' by Eminem came up on my iPod, and it was the perfect beat for the pace I was running," says the recent Michigan State University grad. "Running never felt better than it did at that moment; it was amazing. But next, a song came up that was a totally different pace. It completely threw off my stride. It also made me wonder why I couldn't match all of my music to my running pace."

Leider ran his question by fellow MSU student Benny Ebert-Zavos, a marathon runner. The two found that there were apps on the market that adjust song tempos as a runner's pace changes, but none that categorized music according to tempo. With that, TempoRun was born.

The iOS app, which sells on iTunes for $2.99, helps users run at their ideal pace by categorizing the music in their libraries from level 1 (walking) to 10 (sprinting). Runners select a level, which can be changed with arrows on the simple interface. The app also keeps track of distance, times and calories burned, and even incorporates a streaming service, TempoRun Radio, which provides music at each numbered pace. The app saw 2,000 downloads the first day of launch.