The first interesting revelation is that the iPhone XS has a smaller battery than the one found inside last year's iPhone X -- 10.13Wh compared to 10.35Wh. According to iFixit, the reason for this is that in moving from a design that featured a dual-battery, the iPhone XS uses a single-celled L-shaped battery. In order to create a battery with six corners, Apple had to add notches to the corners to handle thermal expansion, and this in turn reduced the capacity of the battery.
The iPhone XS Max continues to make use of a dual-battery system, and this has a capacity of 12.08Wh.
As for the waterproofing of the new iPhones being bumped up from IP67 to IP68, the iFixit team couldn't find any signs of additional seals or gaskets compared to last year's models, leading them to believe that Apple may have erred on the side of caution and undersold the waterproofing capabilities of the handsets.
iFixit also found a new Apple chip inside the iPhone XS Max -- the Apple 338S00456, which is a new power-management chip.
iFixit gave both the iPhone XS and iPhone XS Max a 6 out of 10 on the repairability scale, down in part to how easy it is to replace the display and battery, but breaking the back glass still leaves you in a world of hurt.
The new Samsung Galaxy Note 9 was just announced and we expect three new iPhones and two Google Pixel phones to launch soon. Now is the time to consider selling your current one before market prices drop or plan to participate in a trade-in program.