Polar Loop 2 vs. Apple Watch vs. Fitbit Alta HR vs. Xiaomi Mi Band 4 vs. Amazfit T-Rex

 
Loop 2
Watch
Alta HR
Mi Band 4
T-Rex
 PolarLoop 2Remove Buy NowAppleWatchRemove Buy NowFitbitAlta HRRemove Buy NowXiaomiMi Band 4Remove Buy NowAmazfitT-RexRemove Buy Now

Basic Info

Suggested Price$120$349$150$25$140
Release20152015201720192019

Activity & Fitness

Calories
Cycling (Bicycling)
Distance
Heartn/a
Oxygen
Sleep
Steps
Swim

Battery

Duration8 days (without notifications)18 hours7 days20 days20 days
Rechargeable

Compatibility

Android
iOS
Windows Phonen/aNA
Macn/aNA
Windowsn/aNA

Connectivity

Bluetooth
Cellular
GPS
NFC
Wi-Fi

Display

Color
Resolutionn/a340 x 272 or 390 x 312128 x 36120x240360 x 360
Sizen/a1.5 inches or 1.65 inches1.4 inches0.95 inches1.3 inches
Touch
TypeLEDAMOLEDOLEDAMOLEDAMOLED

Functions

Audio Speaker
Clock
Phone
Vibration
Voice

Hardware

Accelerometer
Barometer or Altimeter
Ultraviolet Sensor
Water Resistance2 ATMIPX75 ATM5 ATM

Notifications

Phone
Emails
Texts

Software

Operating Systemn/aWatch OSAMAZFIT OSBuild-in
Apps
Music

All Wearables