Polar M400 vs. Fitbit Ionic vs. Fitbit Flex vs. Polar A370 vs. Amazfit T-Rex

 
M400
Ionic
Flex
A370
T-Rex
 PolarM400Remove Buy NowFitbitIonicRemove Buy NowFitbitFlexRemove Buy NowPolarA370Remove Buy NowAmazfitT-RexRemove Buy Now

Basic Info

Suggested Price$200$299$100$179.95$140
Release20142017201320172019

Activity & Fitness

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

Battery

Duration8 hours to 30 days4+ days5 daysUp to 3 days20 days
Rechargeable

Compatibility

Android
iOS
Windows Phonen/aNA
Mac
Windows

Connectivity

Bluetooth
Cellular
GPS
NFC
Wi-Fi

Display

Color
Resolutionn/a348x250NA160 x 80360 x 360
Sizen/a1.42NA1.18 inches1.3 inches
TouchNA
Typen/aOLEDLEDTFT LCDAMOLED

Functions

Audio SpeakerAlerts only
Clock
Phone
Vibration
Voice

Hardware

Accelerometer
Barometer or Altimeter
Ultraviolet Sensor
Water Resistance3 ATM50m1 ATMWR305 ATM

Notifications

Phone
Emails
Texts

Software

Operating Systemn/aFitbit OSNABuild-in
Apps
Music

All Wearables