My first activity tracker, Vidonn X5, worked reasonably well and lasted for over a year, but the subsequent models I tried were all mostly disasters, especially as they added some features like a heart rate monitor that did not work reliably, and worse, their lifetime was poor, lasting only a few days to a few weeks before stopping working. My Xiaomi Mi Band 2 died last week-end, two days after a firmware update which decreased battery life to less than a day, and now refuses to charge. While the HRM was utterly useless, it did count steps fairly accurately, and battery life was good. Sadly, it would only last about two months. So at this stage, it might be worth spending more for a fitness tracker, and Fitbit has unveiled two new models with Charge 2 and Flex 2.
Fitbit Charge 2 includes a 1.5″ OLED touchscreen display, and an heart rate monitor. It also supports step counting and sleep tracking, GPS tracking via your phone, and notifications for calls, SMS, and so on. Battery life is said to be around 5 days per charge.
Fitbit Flex 2 does not come with a display, but instead features notification lights. It has a thinner design, and is suitable for swimming with better waterproofness (up to 50 meters), and swim tracking. Phone notifications are supported via the 5 LEDs, and a vibration motor. Battery is also said to last a mere 5 days between charges.