New Apple Watch teardown reveals it's mostly unchanged from Series 2

Repair manual site iFixit recently released its Apple Watch Series 3 with LTE teardown and revealed that, with the exception of a beefier battery and LTE capabilities, its guts look extremely similar to that of its Series 2 predecessor.

As the iFixit team began their brave and delicate journey to the center of the Apple Watch with an iOpener tool, they noted that "Aside from that ~~status symbol~~ red dot, we'd almost be convinced we're opening a Series 2 again." In fact, they didn't really begin noticing many glaring differences until they got to the battery. The display was mostly unchanged from the Series 2 display, with the exception of the fact that it functions as an LTE antenna. The battery, however, had definitely been augmented to meet the power requirements for LTE:

The Series 3 battery, designated A1848, packs in 1.07 Whr (279 mAh at 3.82 V). That's nearly a 4% increase from the 1.03 Whr battery we found in the Series 2—which itself was a whopping 32% increase over the original Apple Watch's 0.78 Whr cell.

They also noted that the wireless charging coil on the back had been modified for use with most Qi wireless chargers, like the new iPhone 8 and iPhone X.

As the dissection continued, iFixit found "a whole new section of RF chips" that are responsible for the LTE functionality, such as an ST Microelectronics ST33G1M2 32 bit MCU with ARM SecurCore SC300, an Avago chip and a SkyWorks chip. This is all in addition to Apple's new and improved W2 wireless chip that's meant to increase both the battery life and Wi-Fi connection speed of the watch.

In the end, iFixit gave the new Series 3 Apple Watch an overall repairability score of 6/10, stating that tasks like replacing the battery and screen are a bit difficult but fairly straightforward. However, doing board-level repairs will be next to impossible.