I wasn't tuning in to the livestream but ten friends simultaneously messaged me about this watch since I'm "the scuba diving friend." I currently dive with a Shearwater Perdix which syncs to Shearwater's phone and desktop apps with detailed dive info and graphs, and supports cloud-synced dive logs and equipment notes. It also syncs with a wireless transmitter attached to my tanks to plot my air consumption over the course of the dive. Because of all of this, I can't exclusively use the Apple Watch as my dive computer.

That said, it's not uncommon to dive with multiple computers for redundancy if performing multiple dives in a day, and I'm sure Apple's iOS UI for viewing their dive log will be easier to bring up in a pinch than the Shearwater app, which is a clunky Unity app. I'll probably buy it and dive with both.

But I don't imagine existing avid divers will exclusively be using the Apple Watch as a dive computer until it has air integration and dive log notes (if not already). But for casual divers who dive once a year on vacation and don't already have a computer? This is probably an excellent feature.