The software is dissappointing to say the least, although I would characterize it as dangerous.
Although I have owned the watch for sometime, and I dive regularly, I had not used it as a dive watch since most of the dives I do are below the recreational level.
Recently I was at a cave site, and I volunteered to give my backup dive computer to another person since I thought I had another dive computer with me - the Ultra with Oceanic+.
This specific dive was not going to be a deep one (~20m), but it was extended (~150 minutes), and with the possibility of passing through restrictions, so to protect the watch I strapped it inside my drysuit pocket.
At some point, 60 minutes into the dive I decided to take a look at the Ultra. Instead of showing any dive information, it had a screen prompt saying "are you fit to dive?"!
I thought it was rather stupid for the watch to be asking me that after being for 60 minutes through a dive, but I pressed the button and the watch showed me the dive information.
The next day I had to dive the same location, and I followed the same routine. However I did not remove the Ultra from my pocket - not until I finished my dive.
Guess what: because I never answered the question, even though I was diving for 150 minutes, the Oceanic+ application did not record the dive, and did not offer any information for it.
I had to search through the apple watch logs in health.app to realize that the watch did record the dive - Oceanic chose not to offer information.
I have been diving for more than 10 years and own several dive computers (Suunto, Shearwater, Oceanic), and this is the first time that I have seen such complicated, unnecessary, dangerous UI prompts, and choices.
There is no explanation on why they would choose to
a) not show deco obligations just because you did not answer "yes" to their question
b) not record the dive at all
I find the design decisions of the Oceanic software team dangerous, and I would not recommend using this app to anyone. Not unless they treat this thing seriously.