Oppo Watch S2 vs OnePlus Watch 4 specs comparison
These two take quite different approaches. The Watch S2 prioritises low weight, long battery life and health tracking, while the OnePlus Watch 4 offers the richer smartwatch experience and Wear OS ecosystem, at the expense of shorter battery life.
Full comparison
The full record
79 specifications across 6 areas, with 30 genuine differences.
1. Design & display OnePlus Watch 4
Fact
Oppo Watch S2
OnePlus Watch 4
Release date
2026-09-22
2026-04-28
Physical size
8.9 mm thick
47.4 x 47.4 x 11.0 mm
Weight
34.4 g without strap
43 g without strap; 68 g with strap
Material
Stainless steel middle frame; PA + glass-fibre reinforced rear shell
Titanium alloy case, PA with fiberglass bottom case, sapphire crystal, fluororubber strap
Water resistance
5 ATM
5 ATM; IP68; IP69; MIL-STD-810H
Color options
Mountain Shadow Grey, Vibrant Orange, Misty Powder
Midnight Titanium, Evergreen Titanium
Display type
AMOLED
LTPO OLED
Display size
1.46 inch
1.5 inch
Display resolution
464 x 464 pixels, 317 ppi
466 x 466 pixels, 310 ppi
Display brightness
600 nits typical; 1,500 nits outdoors; up to 3,000 nits in supported workout modes
Up to 3,000 nits
Display protection
Glass
Sapphire crystal
2. Battery & charging Oppo Watch S2
Fact
Oppo Watch S2
OnePlus Watch 4
Battery
Rechargeable battery; 339 mAh typical; 330 mAh rated
Rechargeable battery; 646 mAh typical (632 mAh rated)
Battery life
Up to 10 days in long-battery mode; up to 7 days with typical use; up to 4 days with AOD
Up to 5 days smart mode, 3 days heavy use, 16 days power saver
Charging
Integrated magnetic watch charging cable
Charging base with USB-C cable
Charging time
90 minutes
About 75 minutes maximum
3. Sensors & positioning No clear edge
Fact
Oppo Watch S2
OnePlus Watch 4
GNSS type
Built-in dual-band L1+L5 GNSS
Built-in dual-band GNSS
GPS
Yes
Yes
GALILEO
Yes
Yes
GLONASS
Yes
Yes
QZSS
Yes
Yes
Beidou
Yes
Yes
Accelerometer
Yes
Yes
Gyroscope
Yes
Yes
Barometric altimeter
Yes
Yes
Compass
Yes
Yes
Geomagnetic
Yes
Yes
Ambient light sensor
Yes
Yes
Optical heart rate
Yes (upgraded optical sensor; 75% better interference resistance claimed)
Yes
Electrical heart rate
Yes (China model)
Yes
SpO2
Yes
Yes
Temperature
Yes
Yes
Galvanic skin response
No
No
Microphone
Yes
Yes
Speakers
Yes
Yes
Vibration motor
Yes
Yes
4. Health & activity No clear edge
Fact
Oppo Watch S2
OnePlus Watch 4
Steps
Yes
Yes
Distance
Yes
Yes
Calories burned
Yes (includes FatMax estimated fat burned in grams)
Yes
Floors
Yes
Yes
Sports tracking
Yes (100+ sports modes; FatMax on 16+ activities; 65+ strength exercises recognised)
Yes (100+ sports modes)
Sleep
Yes (includes sleep apnoea risk assessment on China model)
Yes
Heart rate
Yes
Yes
HRV
Yes (used in AI workout-readiness analysis)
Yes
Stress
Yes
Yes
Blood oxygen
Yes
Yes
Respiration rate
Yes
Yes
Skin temperature
Yes
Yes
ECG
Yes (China model)
Yes (regional availability)
Blood pressure
No
No
Body composition
No
No
Glucose
No
No
Hydration level
No
No
UV exposure
No
No
Calorie intake
No
No
Hyperglycemia risk assessment
No
No
Arterial stiffness detection
No
Yes
Pulse wave arrhythmia analysis
No
No
5. Smart features OnePlus Watch 4
Fact
Oppo Watch S2
OnePlus Watch 4
Smartphone compatibility
Android and iOS (China model; Android + Android and Android + iPhone dual-phone combinations supported)
Android 9.0+ with GMS 23.45.23+; no iOS or Android Go support
Operating system at launch
ColorOS Watch 17.0.0
OxygenOS Watch 8 + Wear OS 6
Processor
BES2800BP
Qualcomm Snapdragon W5 + BES2800
Storage
4 GB eMMC
32 GB
Bluetooth
Yes
Yes (5.2)
Wi-Fi
No
Yes (2.4/5 GHz)
NFC / connected pay
Yes (unencrypted access cards; regional support varies)
Yes (Google Wallet)
UWB
No
No
Cellular
No
No
Smartphone notifications
Yes (supports dual-phone pairing)
Yes
Bluetooth calling
Yes
Yes
Smartphone music control
Yes
Yes
On-board music storage
Yes
Yes
Voice assistant
Xiaobu Assistant (China)
Gemini / Google Assistant
6. Navigation & safety OnePlus Watch 4
Fact
Oppo Watch S2
OnePlus Watch 4
Maps
Yes
Yes (Google Maps)
Offline maps
No
Yes (Google Maps; software-dependent)
Navigation
Yes (phone-linked navigation information via Fluid Cloud)
Yes (Google Maps)
Emergency SOS
No
Yes (Emergency Rescue)
Satellite SOS
No
No
Fall detection
Yes
Yes
LED flashlight
No
No
Diving
No
No