Fitbit Ionic vs. Garmin 645 Music vs. Fitbit Flex vs. Garmin Forerunner 45 vs. Garmin VivoActive 4

 
Ionic
645 Music
Flex
Forerunner 45
VivoActive 4
 FitbitIonicRemove Buy NowGarmin645 MusicRemove Buy NowFitbitFlexRemove Buy NowGarminForerunner 45Remove Buy NowGarminVivoActive 4Remove Buy Now

Basic Info

Suggested Price$299$450$100$199$349
Release20172018201320192019

Activity & Fitness

Calories
Cycling (Bicycling)
Distance
Heart
Oxygen
Sleep
Steps
Swim

Battery

Duration4+ days7 days5 days7 days8 days
Rechargeable

Compatibility

Android
iOS
Windows PhoneNA
Mac
Windows

Connectivity

Bluetooth
Cellular
GPS
NFC
Wi-Fi

Display

Color
Resolution348x250240 x 240NA208 x 208260 x 260
Size1.421.2 inchesNA1.04 inches1.3ionches
TouchNA
TypeOLEDMIPLEDLCDMIP

Functions

Audio Speaker
Clock
Phone
Vibration
Voice

Hardware

Accelerometer
Barometer or Altimeter
Ultraviolet Sensor
Water Resistance50m5 ATM1 ATM5 ATM5 ATM

Notifications

Phone
Emails
Texts

Software

Operating SystemFitbit OSNABuilt-inWear OS
Apps
Music

All Wearables