Polar M400 vs. Sony SmartBand 2 vs. Xiaomi Mi Band 2 vs. ASUS ZenWatch 3 vs. Xiaomi Mi Band 4

 
M400
SmartBand 2
Mi Band 2
ZenWatch 3
Mi Band 4
 PolarM400Remove Buy NowSonySmartBand 2Remove Buy NowXiaomiMi Band 2Remove Buy NowASUSZenWatch 3Remove Buy NowXiaomiMi Band 4Remove Buy Now

Basic Info

Suggested Price$200$130$23$229$25
Release20142015201620172019

Activity & Fitness

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

Battery

Duration8 hours to 30 days2 days20 hours48 hours20 days
Rechargeable

Compatibility

Android
iOS
Windows Phonen/an/a
Macn/an/a
Windowsn/an/a

Connectivity

BluetoothYes
Cellular
GPS
NFC
Wi-Fi

Display

Colorn/a
Resolutionn/an/an/a400 x 400120x240
Sizen/an/a0.42 inches1.39 inches0.95 inches
Touchn/a
Typen/an/aOLEDAMOLEDAMOLED

Functions

Audio SpeakerAlerts only
Clock
Phone
Vibration
Voice

Hardware

Accelerometer
Barometer or Altimeter
Ultraviolet Sensor
Water Resistance3 ATMIP58IP675 ATM

Notifications

Phone
Emails
Texts

Software

Operating Systemn/an/an/aAndroid Wear 2AMAZFIT OS
Apps
Music

All Wearables