This is beautiful!

I've been using an Apple Watch Ultra with my Pixel using some of the same hacks.

0. I use messaging apps like WhatsApp, and Messenger which are multi device. So I log into them on the home iPhone. (WA finally added 'login as companion device' on iOS only a year ago). 1. Pushover to get notifications from any other apps that don't support multi device. (Signal ugh). I used Buzzkill to do the pushing from the android devices. Very reliable once set up. 2. I use Google Voice for my calls and SMS so that was easy to get on iPhone. (No calls though. The watch doesn't support sip/voip calls except Apple's own FaceTime ugh) 3. I spent a year doing cellular on Watch. I joined various family members' premium plans of the big 3 US networks (as well asany MVNOs like Visible) to use cellular on the watch. I paid ~$10/mo via this route. All good. But I stopped early this year because I found the cellular reliability to be just... piss poor garbage. (This is extensive use across US as well as international travel in Europe and Asia) It really wasn't worth cellular I realized.

4. I use Apple laptops, so the "watch to unlock" feature is useful multiple times a day :)

Really cool project, and thank you for writing it up so well!

My first question is "why" and the post answers that well (my paraphrasing): because Apple Watch is more accurate than anything else on the market, and health can be a matter of life and death.

OP is definitely an open source guy though so even if you'll never buy another Apple product (like myself) it's still a fascinating look at the current state of things!

Project repo is here - https://github.com/abishekmuthian/apple-watch-with-android .