running apps
Illustration: Jose Luis Merino

The App: Cruise Control: Run

$5; iTunes.com

Meet Your New Playlist
No more off-tempo beats or slow-song lulls: The app analyzes your iTunes library and extracts only high-energy tracks with ideal tempos for your stride, then can speed them up or slow them down to match your footfalls.

Personalize Your Stride
Aiming to conquer a seven-minute mile? The pace feature matches songs to your target speed and automatically changes the BPM to get you there—all you have to do is run to the rhythm. If heart rate is more of a concern, the music can also push you to reach that goal.

Track Your Progress
The app logs your time, speed, distance, even calories burned, and provides stats (complete with a map of your route) so you can monitor your improvement. Share your mileage—and the songs that spurred your latest runner's high—on Facebook.

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