Staying fit is important. Even if it seems enjoyable to lie on the couch devouring hours of HBO Go on your iPad, the truth is, when you're exercising, you're happier—there are plenty of scientific studies to back it up.
The good news: Gadgets can fit in with your gym routine. With the right apps, they can even make it better. We tested out dozens of fitness apps, which can help you train for a marathon, stick to a diet, or do a downward-facing dog pose with the precision of a yogi. If you're serious about getting into shape, here's what you should download first.
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It must be said that picking a best fitness app is a bit like comparing toasters to badgers. Different apps, created for different purposes, achieve totally different goals. So we're starting the list with a handful of honorable mentions—apps that were very specific, but great for the purpose they serve. After that, we have just the best all around choices—the all time top five desert island fitness apps.
If you diet: "Lose It!"
Shedding pounds is hard work, but it's easier when you have a plan and a coach. "Lose It!" helps in both of those departments, crunching the numbers on calorie consumption and tracking how much exercise you're doing. Keep a log of what you're eating, how you're working out, so you can stay on track for your goal weight. Free for Android and iOS.
If you stay loose: "Pocket Yoga"
When you start doing yoga, even downward dog is difficult. It requires strength, breathing, focus—and practice. When you can't get to the studio for a class, you can maintain your practice from home with an app that takes you through a full session. Choose from different styles, levels of difficulties, and durations. $3 for Android and iOS.
If you pace your pulse: "Instant Heart Rate" and "Cardiio"
Knowing your heart rate can help you keep in the right zone for fat-burning cardio, and tracking your resting heart rate is a good metric to chart your progress and overall health. Not everybody can afford a fancy heart rate monitor, but it turns out your smartphone has one built in: the camera. Every time your heart beats, there's a subtle change in your skin color, and your phone's camera is sensitive enough to detect it. It's surprisingly accurate! Instant Heart Rate is free for Android; for iOS, Cardiio costs $5.
The Top Five
5th Place: "Workout Trainer"
For some instruction and motivation, Skimble's "Workout Trainer" is rather handy. It has hundreds of workouts to choose from, and you can filter them by how much time you have, what equipment you have access to, what muscle groups you want to work, and your desired intensity level. Photos of each exercise and digitized voices (which are horrible and grating) coach you through the routines.
If you upgrade to a paid subscription (for $3/month or $25/year), the demon voices are swapped out for an actual coach talking you through it. Plus, the photos are replaced with video demonstrations, which are far more useful. Everything syncs with Skimble.com. It's a nicely designed app, but the subscription model is too expensive. For iOS and Android.
4th Place: "JEFIT"
If you're trying to beef up (or build lean muscle), it's important to keep track of your reps, sets, and the weights you're lifting. The gym app "JEFIT" was designed for bodybuilders, who tend to be rather stat-obsessed. The free app has a few pre-designed routines you can follow and edit, or you can make your own from the list of over 500 exercises. Each exercise has an animation and some procedure tips, and they're searchable by what specific muscle you want to work and what equipment you have access to.
It just makes it really easy to log what you did, time your rest between sets, and sync your data with JEFIT.com. The app interface is pretty spartan, but it serves its purpose. Free and $5 pro versions, both on iOS and Android.
3rd Place: "Endomondo"
Endomondo is a great looking, feature-loaded app for outdoor exercise. It can track you while you're doing just about anything, from running and cycling to swimming and windsurfing (somehow). You can find popular routes near you, challenge your friends, or join their teams. The app can connect to heart rate monitors or cycling cadence devices, and it can import data from a FitBit gadget, or stats from the RunKeeper app among many others.