I've been wearing an Oura Ring to track my fitness for 4 years. Here are the pros and cons of the device loved by celebs and business execs.

My Oura Ring tracks my movement and rest across the day, and it is subtle enough to wear on any occasion.

Rachel Hosie

• The Oura Ring is a fitness tracker popular among athletes, business execs, and celebrities.
• Fitness reporter Rachel Hosie has used one for four years and was originally attracted by its look.
• Oura ``Rings provide sleep data, step counts, and menstrual cycle tracking.

When I first learned about a new fitness-tracking smart ring four years ago...