So I took the opportunity to research that question and write up the answer for Money Crashers. In the article, I address such points as:
- What fitness trackers actually do, and how they do it. (For instance, their most famous feature, counting the number of steps you take in a day, is accomplished with an accelerometer. Some of them also have fancy features like a heart rate monitor or a sleep tracker, though it appears these don't always work very well.)
- How much they really change your habits. (Studies on the subject show mixed results; some find people exercise more with them, though only by a modest amount, while others report no change. But they can be useful for other things, like tracking your progress toward a specific fitness goal.)
- What they cost. (Recommended models range from $60 for a modest clip-on to $220 for a pimped-out watch for hardcore athletes.)
- What the alternatives are. (For instance, if you are one of the 318,899,999 people in the U.S. who does own a smartphone, there are apps that can do a lot of what a fitness tracker does for $5 or less. Or you can spend $30 on a simple pedometer, which is more accurate for counting steps.)
- How to decide whether a tracker is for you, and if so, which one to get.
Based on my findings, I've decided that I don't really need one of these little gizmos. I think I probably get at least 7,000 steps a day anyway, and that's more than a study of other women my age found they were getting with fitness trackers, so I suspect the benefits would be minimal. But your mileage (on foot) may vary, so check out the full article to get the skinny:
Are Fitness Activity Trackers & Watches Worth the Money?