Amazfit GTR
Tech specs 
Size47mm - 47.2 x 47.2 x 10.75 mm
42mm - 42.6 x 42.6 x 9.2 mm
MaterialStainless steel, aluminium and titanium case options
ChargingUSB, Magnetic charging
Battery47mm: 410mAh
42mm: 195mAh
Battery life47mm: 24-days battery life with normal use, and up to 74 days in basic watch mode
42mm: 12-days with normal use, and up to 34 days in basic watch mode
Water-resistanceUp to 50 metres (5 ATM)
Weight47mm: 36g (aluminum alloy), 48g (stainless steel), 40g (titanium metal)
42mm: 25.5g
SensorBioTracker PPG, 6-Axis Accelerometer, 3 Axial Geomagnetic Sensor, Air Pressure Sensor, Capacitive Sensor, Ambient Light Brightness Sensor, GPS + GLONASS and NFC
DisplayAMOLED with Corning Gorilla Glass 3 protection
Screen size47mm: 1.39 inches (454x454, 326 ppi)
42mm: 1.29 inches (390x390, 326 ppi)
Colors47mm variant comes in a choice between stainless steel, aluminium and titanium cases. There's also a special Iron Man edition. 42mm variant comes in a choice between starry black, moonlight white, cherry powder, and coral red colours. There's also a Swarovski Edition with crystal encrusted bezels.
OtherPLATFORM: Proprietary
PROCESSOR: N/A
MEMORY: 512 MB of RAM, 4 GB of storage
CONNECTIVITY: Bluetooth 5.0 LE, GPS + GLONASS and NFC
Activity tracking 
StepsYes
DistanceYes
Calories burnedYes
ActivityYes
Floors
SleepYes
Heart rateYes
Stress & recovery
Pulse Ox
Respiration rate
UV exposure
Skin temperature
Galvanic skin response
Hydration level
Calorie intake
GPSYes
Running features
Swimming featuresSWOLF, pace, stroke detection
Other - alerts for arrhythmia and atrial fibrillation
Non-fitness functions 
Smartphone notificationsYes
On-board music storage
Connected payYes
LTE
Links 
Affiliate link*Amazon
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