PULSE O2 WITHINGS
$ 129 withings. com
THIS second- generation activity tracker improves on the original with the addition of a watchband as well as a clip. The O2 lets you check your heart rate and blood oxygen level, but you must take the device out of its band to do so. It tracks steps, elevation and sleep but the screen is almost impossible to see in bright sunlight and the device is not waterproof. Negatives aside, it works well with the accompanying app and other Withings products.