In this Feb. 5 photograph, cardiologist Dr. Sarah Timmapuri, left, looks at data on a smart phone synchronized to a new Fitbit Surge worn by patient Gary Wilhelm, 51, during an examination, in Hackensack, N.J. Wilhelm who works at Hackensack University Medical Center in New Jersey on payroll and finance technology, joined Hackensack’s app test after he suffered a heart attack in October. Credit: Mel Evans / ASSOCIATED PRESS

Despite the attention it’s getting, the Apple Watch isn’t the only wearable gadget gaining fans. Already-established fitness and fashion devices such as ones from Fitbit, Microsoft, Jawbone and Motorola keep improving. If you’re in the market for a fitness tracker or smart watch, what should you look for? Here are the three most –important things:

Is it really wearable? In reviewing the Microsoft Band, I found it to be an ergonomic nightmare. It’s not something I would wear regularly, especially not for sleep tracking. Make sure the device you want is comfortable for extended use.Is this data you need? Will you really use heart-rate information or pedometer data about how much you’ve walked each day? You may find the influx of quantified life data more distracting than enlightening.Am I compatible? Make sure the device you seek will work well with whatever smartphone or computer you intend to pair it up with. Android smart watches aren’t typically a great match for iPhone users, and the Apple Watch is nearly useless if you don’t have an iPhone 5 or newer.

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