There are a few things that prevent the Vivosmart 4 from gaining a five-star review and Best Buy award, namely its lack of GPS and cycling mode. Plus, you can easily make the case that its rivals such as the Fitbit Charge 3 are better looking.

Body Battery; Swim tracking; Slim and lightweight; Not expensive

Could be more attractive; No GPS or cycling mode

I was looking for a device that would be able to monitor my sleep patterns with an added benefit of oxygen levels. What I found with the Vivosmart 4 is an extremely lightweight device that is small and thin enough not to be distracting on the wrist when worn.

I'm a Garmin fan. I chose this product bcs it's smaller & sleek than most activity watches. What I didn't agree with Garmin on this product is you can't switch out the bands. Also, if your a swimmer this product isn't for you. This watch can go with you on your swim, but it won't track it for you.

A new style, metrics, and sensors in the Vivosmart 4 shows Garmin is willing to keep its fitness trackers fresh and exciting.

Slim; fashionable design; Affordable price; Body battery; Pulse ox

Small display for notifications; No GPS or connected GPS

The appetite for fitness trackers may be slowly diminishing as smartwatches start to displace them, but for the time being there's plenty of juice for Garmin, Fitbit and others to squeeze out of the market.

Body Battery works well; Pulse ox could be handy for some; Beautiful design

No GPS; Smart notifications messy; Interface is twitchy

The Vivosmart 4 is a run-of-the-mill tracker with a few noteworthy features but not enough to win an award

Detailed sleep tracking; accurate step counting; can be helpful for dieting

No activity reminders; so-so screen visibility; No activity reminders; so-so screen visibility

Tracking sleep, stress and energy levels is endlessly interesting with the sleek, stylish Vivosmart 4, but an unresponsive display and inaccurate run tracking proved frustrating.

Slim; stylish design; Body Battery feature; Advanced health tools

Inaccurate run tracking; Small; unresponsive screen

The Garmin Vivosmart 4 is a simple, slimline, swimproof fitness tracker that allows you to monitor activities, count your steps, check your heart rate and track your sleep.

Slimline and swimproof; Heart rate monitor; Range of modes

Screen is pretty small; No GPS

Fitness tech companies, particularly Fitbit and Garmin, want to monitor the level of oxygen in your blood. It's a metric that could help spot signs of sleep apnea and other breathing-related problems, so companies have been scrambling to perfect their SpO2 sensors and incorporate this data into...

Attractive; lightweight design; Informative Body Battery metric; Great battery life; even with SpO2 sensor on during sleep; On-device music controls; Works with Android and iOS devices; Syncs with Apple Health

Not as many on-device workouts to track; No connected GPS; No NFC for Garmin Pay; Few communication tools (only Android users will get quick replies for messages); No female health tracking features; Cannot switch out bands

The £119/$129 wearable is a direct challenge to the new and is thinner and lighter than its predecessor, and is more stylish thanks to the metallic accents around the display. The new tracker, which succeeds the excellent , also promises a week-long battery life and water resistance, making it safe...