One of its other new features is the ability to gauge your energy levels based on your stress, heart rate variability, sleep quality and activity. A high "Body Battery energy" means Vivosmart 4 thinks you'll be able to handle heavier tasks like working out, while a low one means the device believes you need to take it easy. To make that new feature possible, Garmin has redesigned its heart rate sensor to make it more powerful and made sure the device has all-day stress tracking, which comes with a relax reminder function that suggests you take a breather if your stress levels go through the roof.
Vivosmart 4 is pool- and shower-safe and can run for up to seven days between charges. With a retail price of $130, it's $20 cheaper than the Charge 3, though take note that it looks like it has a slimmer display than its rival. The device is now available for purchase worldwide from Garmin's website and from various retailers, including Amazon and Target.
According to engadget