Apple Watch Series 3 teardown finds slightly bigger battery, few other changes beyond LTE

The LTE version of the Series 3 includes "a whole new section" of RF chips, including an ST Microelectronics part believed to be the eSIM, iFixit said. Other parts come from the likes of Avago and SkyWorks, and of course Apple, which has touted its W2 wireless chip as providing better power effiency and faster Wi-Fi connections.

The Series 3 battery is a 1.07 watt-hour unit, up almost 4 percent from the 1.03 watt-hours in the Series 2. That indicates that Apple is relying heavily on chip improvements elsewhere — such as the W2 — to compensate for the power demands of LTE.

The Watch's barometric altimeter has been relocated to the case, next to the microphone. Notably, while an altimeter was present in the Series 2, Apple didn't make an announcement of the technology until the newer model.

iFixit gave the Series 3 a 6 out of 10 on its repairability scale, suggesting that while most logic board repairs are impossible and replacing component cables involves microsoldering, owners can theoretically replace the screen and battery as long as they have the right tools.

The product first hit shelves and doorsteps on Friday. The company is already trying to fix a problem with unauthenticated Wi-Fi networks which can prevent a Watch from connecting to LTE.