Motivating yourself to move, or keep moving, might take a little help, maybe from an up-tempo song with a catchy chorus. A neat iPhone app called Spring Moves ($3.99 per month; $19.99 per year [editor's note: price updated Feb. 2015]) (its official name is "Spring - Workout Music for Running, Power Walking & Exercising") plays music designed to help you keep your pace up until the end of your workout. You tell the app your steps per minute or RPMs for cycling, and it selects music that will be ideal for your pace. With more than 30,000 songs across a number of genres, it's a great way to explore new music while also burning some calories.

Like a lot of workout apps, Spring Moves supports a wide range of exercises: running, walking, bicycling, rowing, interval training, swimming (I guess you need a water-tight iPhone case and headphones for that?), and a generic "other" category for everything else. You can work out outside and use your iPhone's GPS to automatically track your route, distance, speed, and so forth, or you can work out inside on a treadmill or stationary bike with the GPS off.

The app doesn't have all features I'd want if I were very conscientious about collecting every data point under the sun, but if you're just looking to explore new music and have playlists generated for you automatically while you exercise and track your workout, it's pretty neat. One more caveat: All the music is streaming, not downloaded locally, which will tax your battery and also could cause a big dent in your data plan.

Price and Getting Started

Spring Moves, which is only available on iPhone, is free to download, and new users get to try it out for free with five hours of music included, no credit card required. That's a big plus in my book.

Once your free trial expires, you'll have to pay either $3.99 a month or $19.99 per year for the service. Without a paying membership, you can't stream any of the music, so you could still use the app to track your activities, but it wouldn't make much sense, seeing as the whole point of the app is the music.

The app works like many other activity-tracking apps. You set up an account with basic information about yourself (height, age, weight, sex), but Spring Moves has a few extra selections. For instance, you need to tell the app how many steps you take in a minute or your RPMs if cycling. It will suggest an average number if you're not sure, but it also has a tool that lets you figure it out. The testing tool simply has you move at your pace and tap the screen each time your foot lands (or completes a rotation on a bike). It takes around 10 seconds or so for the app to figure out your rhythm, and it uses that information to pick good running songs for you.

When you're ready to work out, you select your activity and set out, just as in any other exercise-tracking app, such as Runtastic PRO or Map My Ride. While you work out, the app and phone track your route on a map and keep track of how fast you go. Audio feedback will announce your distance, time, pace, and other information you select at whatever interval you set as well (time or distance).

The app automatically plays songs that match your tempo, and you can change it mid-workout if you're flagging or suddenly have a burst of energy. For interval training, you set two different tempos ahead of time: one for high intensity and one for low intensity, and you add a time for each variation, too.

At the end of your activity, when you see the completed map of an outdoor workout, you see song markers on the map where a new song started. Tap any music note icon, and details of the song appear so you can know what you heard. Neat. You can also view all the songs in list view, and you can toggle the artists to play never, a little, or a lot.

Spring vs. Other Runners Apps

Among cycling-specific apps, my favorite is Cyclemeter, an Editors' Choice, in part because it gives you just about every data point you could imagine, and its price is competitive with other apps (if it were supremely expensive, it would be another story). I'm also a big fan of Runtastic Road Bike PRO.

"But what about Strava?" you say. I like Strava quite a bit, but because it's more about being competitive than anything else, I think of it as being somewhat separate from other straightforward tracking apps.

I think of Spring Moves as being something slightly different from a straightforward running and bicycling app. Spring Moves is really about the music, and it has a pretty good selection. Although I'm not a huge music dork, I recognized about half the artists and songs that turned up during my activities. (To give you an idea—and laugh if you will—but I had never heard of New Boyz, Tove Lo, Against Me!, or Travis Barker. But I did know Weezer, Jay-Z, Nicki Minaj, The Black Keys, and plenty of others.)  The range is great, with pop, hip hop, electronic dance music, and more. The neat thing is that you can toggle all these different genres of music in the app, the same as you can toggle specific artists, so that they play a little, often, or not at all. 

You can skip songs without limits, but only from the phone's screen or lock screen—not from remote earphone controls, which I would prefer. Another feature missing from my point of view was elevation tracking. Very detailed activity-tracking apps always include elevation changes, which is important to understand how your running and cycling pace changes.

I would have also liked a delay-start button, which a lot of exercise apps have. This feature lets you start an activity after a few seconds, and you set the time limit. It gives you time to tuck your phone away or hop on your bike before you take off. Spring Moves does give you four beeps before it begins recording, but that's not always enough time. 

One final thing I'd love to see added to the app is a workout that goes for a set length of time, such as a 25-minute run, so that Spring Moves could automatically include a warmup and cool down song. Or I'd even love some kind of option to indicate I want the tempo to gradually increase, rather than have to manually adjust it.

Pump It

I like Spring Moves a lot because it exposed me to new music that I wouldn't have necessarily ever put on a playlist on my own, and it finds songs with the right beat for your workout. If you're seriously picky about your music, you'd probably want to stick with a running and bicycling app that lets you play your own playlists from another app, such as Editors' Choice Runtastic PRO. You can try Spring Moves for free, with five hours of music included and no credit card required, and I encourage you to give it a spin. If you like it, you'll have to pay, however. There isn't much of a point to using the app without the music.

For more fitness app recommendations, see The 25 Best Fitness Apps.