Device Selection Guide
Make an informed decision between LTE smartwatches and compact smartphone setups, recognizing trade-offs in battery life, app compatibility, and audio quality.
Fitbit FB521GLBM-US Advanced Health and Fitness Smartwatch
Available Options
Price history by variant
Volatility: MediumModel overview
3
Price range
$219.99
—
$220.41
Variant spread:
Low
Available variants
Key differences
Product Dimensions
1.57 x 0.47 x 1.57 inches; 7.05 ounces • 1.57 x 0.47 x 1.57 inches; 6.74 ounces • 1.57 x 0.47 x 1.57 inches; 1.3 ounces
batteries
1 LR44 batteries required. (included) • 1 Lithium Ion batteries required. (included)
How to choose
- Start with your budget: the visible price spread across variants is about 0%.
Trade-offs
Product Dimensions
Different values may change day-to-day usage profile depending on your priorities.
batteries
Different values may change day-to-day usage profile depending on your priorities.
Close variants
Most variants are close to each other; choice is often driven by price and availability.
Starting from $219.99
Last price update: 3/11/26
This advanced health and fitness smartwatch offers comprehensive wellness monitoring with features like all-day stress detection using cEDA technology, an ECG app for atrial fibrillation assessment, and personalized sleep profiles. It includes built-in GPS for tracking activities, a workout intensity map, and a battery life exceeding six days. The device provides detailed health insights, supports various exercise modes, and offers connectivity options for calls, texts, and notifications. It is water-resistant and customizable with interchangeable clock faces.
