Cardio Smackdown's challenge feature is neat, but you can also workout solo (and you might have to, if none of your friends are up for working out). In this case, you'll see all of your stats: Elevation gain, speed, distance, steps, calories, peak altitude, and time. While a solo workout doesn't exactly make cardio fun, Cardio Smackdown's in-depth stats can be useful.
Get creative with your cardio
Not all cardio-fun-making apps have to be specifically designed for that purpose. In fact, some of my go-to gym apps aren't designed for fitness freaks at all. For example, I love streaming Doctor Who and Law and Order: SVU on Netflix ($8 a month; Android and iOS), or catching up on Saturday Night Live on Hulu Plus ($8 a month; Android and iOS). A movie or a TV episode is often the perfect length for a good cardio workout. I also like to read magazines on my iPad with Zinio (subscription price varies; Android and iOS), and trust me: It's a lot easier to swipe through pages while running than it is to physically turn them.
Finally, if you're willing to spend a little more and tote some hardware with you to the gym, Blue Goji's Goji Play system ($100; hardware paired with an app for iOS) actually makes cardio into a game. Although the system still needs a little work, it's polished enough to keep you distracted from what you're actually doing (running, and sweating like a pig).
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