Fitbit Charge 4
Tech specs 
SizeDevice Dimensions: 42.7mm x 28.8mm x 12.5mm
One size (small and large bands included)
MaterialBuilt of more lightweight material including an aerospace grade aluminum case and Corning Gorilla Glass 3 display. The housing and buckle are made of anodized aluminum.
ChargingUSB
BatteryLithium-polymer
Battery lifeup to 7 days, or up to 5 hours with GPS.
Water-resistance5 ATM
Weight30 grams
Sensor3-axis accelerometer, Optical heart rate monitor, Pulse Ox, GPS, Vibration motor, NFC chip for Fitbit Pay, Altimeter, Bluetooth LE (BLE)
DisplayOLED full touchscreen, TFT
Screen size35.8mm x 22.7mm
ColorsMultiple
OtherCharge 4 stores your stats and data for 7 days in between the times you sync your tracker.
Activity tracking 
StepsYes
DistanceYes
Calories burnedYes
ActivityYes
FloorsYes
SleepYes
Heart rate24/7
Stress & recovery
Pulse OxYes
Respiration rate
UV exposure
Skin temperature
Galvanic skin response
Hydration level
Calorie intake
GPSYes
Running features
Swimming features
Other Guided breathing, Female Health Tracking, Spotify control
Non-fitness functions 
Smartphone notificationsYes
On-board music storage
Connected payYes
LTE
Links 
Affiliate link*Amazon
Read moreReview
*Disclosure: We are a professional review site that receives a small commission from sales of certain items, but the price is the same for you. See our affiliate disclosure page for more details.
**All tech specs and images on this page come from manufacturers. These may change over time as manufacturers sometimes update their devices. While we cannot guarantee absolute accuracy of information on this page, we promise to review this content regularly and do our best to bring you the most up-to-date information. To be absolutely sure of tech specs of a particular device, we recommend checking the manufacturer’s website.