The teardown reveals that Apple Watch Series 3 with LTE features a 4% larger 279mAh battery compared to the Series 2 Apple Watch. The array of new RF chips required for LTE connectivity on the Apple Watch Series 3 are located at the very bottom along with a barometric pressure sensor which sits next to an air vent hole. Other components used inside Apple’s latest wearable are largely the same as their predecessor including the PPG heart rate sensor array.
Overall, iFixit gives the new Apple Watch a repairability score of 6 out of 10, the same as its predecessor. It notes that while difficult, screen replacements are still possible on the Apple Watch Series 3 along with battery replacement. However, replacing any component cable on the wearable won’t be possible as they require microsoldering.
The Apple Watch Series 3 went on sale alongside the iPhone 8 and iPhone 8 Plus on September 22, though initial buyers have been marred with various LTE connectivity issues with the wearable.