Feature | Apple Watch Series 9 | Apple Watch Series 8 | Apple Watch Series 7 | Apple Watch Series 6 | Apple Watch Series 5 | Apple Watch Series 4 |
Case Size | 41mm or 45mm case | 41mm or 45mm case | 41mm or 45mm case | 40mm or 44mm case | 40mm or 44mm case | 40mm or 44mm case |
Display | Always-On Retina LTPO OLED display, up to 2000 nits | Always-On Retina LTPO OLED display, up to 1000 nits | Always-On Retina LTPO OLED display, up to 1000 nits | Always-On Retina LTPO OLED display, up to 1000 nits | Always-On Retina LTPO OLED display, up to 1000 nits | Retina LTPO OLED display, up to 1000 nits |
Materials | Ion-X glass display on aluminum cases; sapphire crystal display on stainless steel cases | Ion-X glass display on aluminum cases; sapphire crystal display on stainless steel cases | Ion-X glass display on aluminum cases; sapphire crystal display on stainless steel and titanium cases | Ion-X glass display on aluminum cases; sapphire crystal display on stainless steel and titanium cases | Ion-X glass display on aluminum cases; sapphire crystal display on stainless steel, titanium, and ceramic cases | Ion-X glass display on aluminum cases; sapphire crystal display on stainless steel cases |
Connectivity | GPS and GPS + Cellular models | GPS and GPS + Cellular models | GPS and GPS + Cellular models | GPS and GPS + Cellular models | GPS and GPS + Cellular models | GPS and GPS + Cellular models |
Processor | S9 SiP with 64-bit dual-core processor; W3 wireless chip; second-generation Ultra Wideband chip27 | S8 SiP with 64-bit dual-core processor; W3 wireless chip; U1 chip (Ultra Wideband)27 | S7 SiP with 64-bit dual-core processor; W3 wireless chip; U1 chip (Ultra Wideband)27 | S6 SiP with 64-bit dual-core processor; W3 wireless chip; U1 chip (Ultra Wideband)27 | S5 SiP with 64-bit dual-core processor; W3 wireless chip | S4 SiP with 64-bit dual-core processor; W3 wireless chip |
User Interaction | Digital Crown with haptic feedback; side button; double tap gesture; on-device Siri | Digital Crown with haptic feedback; Siri | Digital Crown with haptic feedback; Siri | Digital Crown with haptic feedback | Digital Crown with haptic feedback | Digital Crown with haptic feedback |
Sensors | Temperature sensor,7 blood oxygen sensor;4 electrical heart sensor and third-generation optical heart sensor | Temperature sensor,7 blood oxygen sensor;4 electrical heart sensor and third-generation optical heart sensor | Blood oxygen sensor;4 electrical heart sensor and third-generation optical heart sensor | Blood oxygen sensor;4 electrical heart sensor and third-generation optical heart sensor | Electrical heart sensor and second-generation optical heart sensor | Electrical heart sensor and second-generation optical heart sensor |
Heart notifications | High and low heart rate notifications, irregular rhythm notification, and ECG app33; sleep stages | High and low heart rate notifications, irregular rhythm notification, and ECG app33; sleep stages | High and low heart rate notifications, irregular rhythm notification, and ECG app33; sleep stages | High and low heart rate notifications, irregular rhythm notification, and ECG app33; sleep stages | High and low heart rate notifications, irregular rhythm notification, and ECG app33; sleep stages | High and low heart rate notifications, irregular rhythm notification, and ECG app33; sleep stages |
Emergency Features | International emergency calling,10 Emergency SOS,9 Crash Detection,9 and Fall Detection | International emergency calling,10 Emergency SOS,9 Crash Detection,9 and Fall Detection | International emergency calling,10 Emergency SOS,9 and Fall Detection | International emergency calling,10 Emergency SOS,9 and Fall Detection | International emergency calling,10 Emergency SOS,9 and Fall Detection | Emergency SOS9 and Fall Detection |
Water Resistance | Water resistant 50 meters12 | Water resistant 50 meters12 | Water resistant 50 meters12 | Water resistant 50 meters12 | Water resistant 50 meters12 | Water resistant 50 meters12 |
Dust Resistance | Dust resistant (IP6X)25 | Dust resistant (IP6X)34 | | | | |
LTE, Wi-Fi, Bluetooth | LTE and UMTS,14 Wi-Fi 4 (80211n), and Bluetooth 5.3 | LTE and UMTS,14 Wi-Fi 4 (80211n), and Bluetooth 5.3 | LTE and UMTS,14 Wi-Fi, and Bluetooth 5.0 | LTE and UMTS,14 Wi-Fi, and Bluetooth 5.0 | LTE and UMTS,14 Wi-Fi, and Bluetooth 5.0 | LTE and UMTS,14 Wi-Fi, and Bluetooth 5.0 |
GPS, Compass, Altimeter | GPS/GNSS, compass, and always-on altimeter | GPS/GNSS, compass, and always-on altimeter | GPS/GNSS, compass, and always-on altimeter | GPS/GNSS, compass, and always-on altimeter | GPS/GNSS, compass, and barometric altimeter | GPS/GNSS and barometric altimeter |
Speaker and mic | Built-in speaker and mic | Built-in speaker and mic | Built-in speaker and mic | Built-in speaker and mic | Built-in speaker and mic | Built-in speaker and mic |
Capacity | 64GB capacity | 32GB capacity | 32GB capacity | 32GB capacity | 32GB capacity | 16GB capacity |
Charging | Fast charge time19 | Fast charge time35 | Fast charge time | | | |