Amazon.com: Motiv Ring Fitness, Sleep and Heart Rate Tracker for iPhone and Android - Waterproof Activity and HR Monitor - Calorie and Step Counter - Pedometer. Ring Sizing Set and Redemption Kit
Smallest Activity Tracker - Best Buy
New 4G LTE Smallest GSM Tracking Chip for Kids/Pets/Car/Bike Mini GPS Tracker Anti-lost Personal Locator
Fitbit's new Alta HR is the smallest fitness tracker to include a heart rate sensor
Smallest Activity Tracker - Best Buy
Sony's Fitness Tracker Is Smallest Ever | CES 2014 - YouTube
Amazon.com: Minimalist Round Smart Watch for Women Men, World Smallest 1.04" AMOLED Touch Screen Stainless Steel Smartwatch, Answer/Make Call, Smart Notification, Fitness Tracker and Free Steel Band (Black) : Electronics