Jawbone Up Move Activity Tracker for Smartphones - Retail Packaging
While usually worn on the wrist, it is compatible with an official Fitbit Clip accessory .
Tracks steps, calories, and sleep. It is widely considered the best beginner-friendly tracker for its ease of use and accurate app. Xiaomi Smart Band 9 (with Pendant/Clip Accessory)
This is a highly affordable "capsule" style tracker.
: A smart ring that tracks everything from your finger. It is the most discreet alternative for sleep and activity tracking without a traditional "device" look.