| Apple Watch Series 1 | Apple Watch Series 2 | Apple Watch Series 3 | Apple Watch Series 4 | |
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| Tech specs | ||||
| Size | 38.6mm x 33.3mm x 10.5mm (H x W x D) 32.0mm x 35.9mm x 10.5mm (H x W x D) | 38.6mm x 33.3mm x 10.5mm (H x W x D) 32.0mm x 35.9mm x 10.5mm (H x W x D) | 38.6mm x 33.3mm x 10.7mm (H x W x D) 32.0mm x 35.9mm x 10.7mm (H x W x D) | 40 mm (band fits 130-200mm wrists) 44 mm (band fits 140-210mm wrists) |
| Material | Steel, Aluminum, or 18k Gold (case), Sapphire Crystal | Steel, Aluminum, Ceramic, Sapphire Crystal | Aluminum, Ceramic (White, Black), Sapphire Crystal, Gold Aluminium, Stainless Steel (Silver, Black) | Sapphire crystal and ceramic back. |
| Charging | inductive charging | inductive charging | wireless charging | Wireless charging |
| Battery | Lithium-ion | Lithium-ion | Lithium-ion | Lithium-ion |
| Battery life | 18 hours | 18+ hours | 18+ hours | 18+ hours |
| Water-resistance | IPX7 (3 metres) | 5 ATM (50 metres) | 5 ATM (50 metres) | 5 ATM (50 metres) |
| Weight | 25 grams to 69 grams depending on the model | 25 grams to 69 grams depending on the model | 53 grams | Case weight: 30.1g (for 40mm version); 36.7g (for 44mm version) |
| Sensor | Ambient light, Heart rate sensor, accelerometer, and gyroscope. | Ambient light, Heart rate sensor, accelerometer, gyroscope, built-in gps. | Ambient light, heart rate sensor, accelerometer, gyroscope, GPS, barometric altimeter | Ambient light, optical heart rate sensor, Electrical heart sensor, improved accelerometer up to 32 g‑forces, improved gyroscope, GPS (GLONASS, Galileo, and QZSS), barometric altimeter, ambient light sensor |
| Display | Retina display with Force Touch | OLED Retina display with Force Touch Ion-X glass (strengthened glass) | OLED Retina display with Force Touch Ion-X glass (strengthened glass) | LTPO OLED Retina display with Force Touch (1000 nits), Ion-X strengthened glass |
| Screen size | 38mm: 340x272 pixels 42mm: 390x312 pixels | 38mm: 340x272 pixels 42mm: 390x312 pixels | 38mm: 340x272 pixels 42mm: 390x312 pixels | 44mm: 977 sq mm display area (368 x 448 pixel resolution) 40mm: 759 sq mm display area (324 x 394 pixel resolution) |
| Colors | Gold, Rose Gold, Space Gray, Silver, Black. Straps vary by editions. | Gold, Rose Gold, Space Gray, Silver, Black. Straps vary by editions. | Gold, Rose Gold, Space Gray, Silver, Black. Straps vary by editions. | A number of aluminum finishes anodized in silver, gold and space gray. You can also pick up the device in gold stainless steel with a matching Milanese band, joining the silver and space black stainless steel models. |
| Other | PLATFORM: watchOS PROCESSOR: Dual-core Apple S1P MEMORY: 8 GB, 512 MB RAM CONNECTIVITY: WiFi, Bluetooth, NFC | PLATFORM: watchOS PROCESSOR: Apple S2, dual-core MEMORY: 512 RAM, 8GB storage (2GB of which can be used for music) CONNECTIVITY: Bluetooth 4.0, NFC, WiFi | PLATFORM: watchOS PROCESSOR: S3 dual-core processor MEMORY: 512 RAM, 16GB storage CONNECTIVITY: Bluetooth 4.0, NFC, WiFi, LTE and UMTS cellular radio | PLATFORM: watchOS PROCESSOR: S4 with 64-bit dual-core processor, W3 Apple wireless chip MEMORY: 512 RAM, 16GB storage CONNECTIVITY: Bluetooth 4.0, NFC, WiFi, LTE and UMTS cellular radio |
| Activity tracking | ||||
| Steps | Yes | Yes | Yes | Yes |
| Distance | Yes | Yes | Yes | Yes |
| Calories burned | Yes | Yes | Yes | Yes |
| Activity | Yes | Yes | Yes | Yes |
| Floors | Yes | Yes | ||
| Sleep | ||||
| Heart rate | Yes | Yes | Yes | Yes |
| Stress & recovery | ||||
| UV exposure | ||||
| Skin temperature | ||||
| Galvanic skin response | ||||
| Hydration level | ||||
| Calorie intake | ||||
| GPS | Yes | Yes | Yes (GPS,GLONASS, Galileo, and QZSS) | |
| Running features | Watch displays up to 5 metrics during your run (time, distance, current pace and average pace, heart rate, active calories or total calories). | Watch displays up to 5 metrics during your run (time, distance, current pace and average pace, heart rate, active calories or total calories). | Watch displays up to 5 metrics during your run (time, distance, current pace and average pace, heart rate, active calories or total calories). | |
| Swimming features | Pool swim and open water swim. At the end of a swim, the watch displays the time of day the activity took place, dominant stroke used (auto-detection is used), distance, workout time, pool length, laps completed, average pace, average heart rate, and both active and total calories burned, as well as the weather at your location. | Pool swim and open water swim. At the end of a swim, the watch displays the time of day the activity took place, dominant stroke used (auto-detection is used), distance, workout time, pool length, laps completed, average pace, average heart rate, and both active and total calories burned, as well as the weather at your location. | Pool swim and open water swim. At the end of a swim, the watch displays the time of day the activity took place, dominant stroke used (auto-detection is used), distance, workout time, pool length, laps completed, average pace, average heart rate, and both active and total calories burned, as well as the weather at your location. | |
| Other | - ECG monitor - irregular heart rate detection - low or high heart rate alerts - fall detection | |||
| Non-fitness functions | ||||
| Smartphone notifications | Yes | Yes | Yes | Yes |
| On-board music storage | Yes | Yes | Yes ( Stream Apple Music direct to watch) | Yes (Stream Apple Music direct to watch) |
| Connected pay | Yes | Yes | Yes | Yes |
| LTE | Yes | Yes | ||
| Links | ||||
| Affiliate link* | Amazon | Amazon | Amazon | Amazon |
| Read more | Review | Article | Article | Article |
**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.