Teardown of Apple Watch shows sensor could measure blood oxygen levels

That's one of the findings from iFixIt, which disassembled an Apple Watch Sport Edition on the day the wearables started shipping to customers.

U.S. government regulations may prevent Apple from allowing the watch to capture blood oxygen data, according to iFixIt, whose website lets people offer each other advice on how to fix a variety of things, including computer hardware. The site is also known for breaking apart Apple's new products as soon as they go on sale.

People eager to perform their own fixes on the Apple Watch may have to stick with swapping out the watch bands. That's the easiest repair to make on the device and only entails pressing a button to release the peg holding the bands in place.

The battery is also easy to remove and is secured with only a "mild adhesive." Accessing the battery, though, requires removing the display, a process that is difficult but not impossible, iFixIt said. The challenge is disconnecting the display cables, which are under a bracket. Apple has said that the watch's battery is replaceable.

However, to reach the watch's other internal components iFixIt had to employ a "destructive process" that required cutting cables, breaking soldered connections and removing adhesive. The tiny screws Apple used to secure components would also hinder do-it-yourself repair efforts. The watch's S1 processor is covered in a "solid block of plasticky resin," making board-level repairs "impossible."

The breakdown may end speculation that Apple would allow people to swap out and upgrade the watch's internal components.

"Stripping out the internals will be difficult and time-consuming -- not the sort of thing your local Genius is equipped to handle," said iFixIt.

Despite the challenges of getting to the watch's innards, iFixIt, which assigns devices a repairability score from one to 10, gave the wearable a five.

As has been reported, the Apple Watch contains a diagnostic port. However, iFixIt couldn't figure out how to remove the door covering the port without taking apart the entire watch. Apple most likely has an easier way to take off the door, according to iFixIt.

Fred O'Connor writes about IT careers and health IT for The IDG News Service. Follow Fred on Twitter at @fredjoconnor. Fred's e-mail address is fred_o'connor@idg.com