Compare Apple Watch models


10.7mm thin			11.4mm thin

64-bit dual-core S4 processor Up to 2x faster than S3 processor			Dual-core S3 processor

Electrical heart sensor (ECG app)¹

Second-generation optical heart sensor			Optical heart sensor

Fall Detection

Digital Crown with haptic feedback			Digital Crown

Finishes

Features
GPS, GLONASS, Galileo and QZSS Barometric altimeter Water resistant 50 metres² Electrical heart sensor (ECG app)¹ Optical heart sensor Improved accelerometer up to 32 G-forces Improved gyroscope Ambient light sensor Speaker 50 per cent louder Microphone Apple Pay GymKit Capacity 16GB Ceramic and sapphire crystal back			GPS, GLONASS, Galileo and QZSS Barometric altimeter Water resistant 50 metres² Optical heart sensor Accelerometer up to 16 G-forces Gyroscope Ambient light sensor Speaker Microphone Apple Pay GymKit Capacity 8GB Composite back

Display
44mm 368x448 pixels 977 sq mm display area			42mm 312x390 pixels 740 sq mm display area
40mm 324x394 pixels 759 sq mm display area			38mm 272x340 pixels 563 sq mm display area
LTPO OLED Retina display with Force Touch 1,000 nits brightness			OLED Retina display with Force Touch 1,000 nits brightness

Chip
S4 with 64-bit dual-core processor Up to 2x faster processor			S3 with dual-core processor
W3 Apple wireless chip			W2 Apple wireless chip

Power
Built-in rechargeable lithium-ion battery Up to 18 hours³			Built-in rechargeable lithium-ion battery Up to 18 hours⁴
Magnetic charging cable			Magnetic charging cable
USB power adapter			—

1.The ECG app requires watchOS 5.2 or later and iOS 12.2 or later, and is not intended for use by people under 22 years old.
2.Apple Watch Series 3 and Apple Watch Series 4 have a water resistance rating of 50 metres under ISO standard 22810:2010. This means that they may be used for shallow-water activities like swimming in a pool or ocean. However, they should not be used for scuba diving, waterskiing or other activities involving high-velocity water or submersion below shallow depth.
3.Apple Watch All-Day Battery Life testing was conducted by Apple in August 2018 using pre-production Apple Watch Series 4 (GPS) paired with an iPhone; all devices were tested with pre-release software. Battery life varies by use, cellular coverage, configuration and many other factors; actual results will vary. See www.apple.com/ie/batteries and www.apple.com/ie/watch/battery.html for more information.
4.Apple Watch All-Day Battery Life testing was conducted by Apple in August 2018 using shipping Apple Watch Series 3 (GPS) paired with an iPhone; all devices were tested with pre-release software. Battery life varies by use, configuration and many other factors; actual results will vary. See www.apple.com/ie/batteries and www.apple.com/ie/watch/battery.html for more information.

Summary