While you can check out your daily activity progress on your watch, I often catch myself absentmindedly opening the Activity app on my iPhone just to gaze at the large, colorful graphs of my data. How many steps did I take? (Step count is only shown in the iPhone app, strangely, not in the Activity app on the watch itself.) How many miles did I run? What was my pace per mile? How many calories have I burned? What was my heart rate? My entire being is quantified in blue, pink, and green charts.
Just counting steps? Then Activity is enough. But if you want to shift the watch into high gear, open the Workout app on your wrist before you hit the gym (or the road). There are eight different workouts available, which includes the usual suspects like indoor/outdoor running and walking, cycling, and elliptical work, plus an "other" option for tracking things like CrossFit, yoga, and other activities. Those other workouts are tracked as if they were brisk walks, which isn't ideal, but will hopefully improve in future iterations of the watch's OS.
Opening the Workout app puts the watch's accelerometer and heart rate sensor to work so you get an accurate picture of how intense your exercise is and how many calories you're burning. This is where the watch really shines: Raise your wrist during a run and immediately see your heart rate, pace per mile, how much time has elapsed, and how close you are to your mileage goal. You can even see all of this data without your iPhone with you.
Running without my iPhone was actually no different than running with it (except the lack of Spotify), which was a huge concern for me when I pre-ordered the Watch Sport. The device relies on your phone for GPS, but the Workout app doesn't map your run, so the lack of GPS is only important when you want your mileage to be exact. The watch overestimated my mileage when I left my phone behind, but not by much. The device even has local storage for music, but you'll need Bluetooth headphones to take advantage of it. (If you have a recommendation for a pair you use while running, let us know in the comments.)
We still need to pit the watch's heart rate sensor against a chest strap, which is considered the most accurate way to measure heart rate during exercise, so check back for that throwdown in the coming weeks. I found the watch's heart rate sensor to be a big improvement over other fitness trackers for real-time data. And it will be interesting to see what app developers do with the sensors when Apple opens them up to third parties down the line.
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