Hi @zzGordon!
I’ve been really wanting to try this new macOS feature! I haven’t had the courage yet to install the macOS beta though. I need to still be able to ship Arc builds to the App Store, and sometimes when you install a macOS beta Apple will reject any builds you send, due to being built on pre-release software 
My understanding of the new feature so far is that … it shouldn’t be possible for Arc to make it not work. It looks to me like all apps on the phone should just work normally, with no changes. But if you see anything different happen, definitely let me know!
Same! I was really excited for Apple’s Journal app, when that was announced. But was disappointed to see that it didn’t really have much integration with other apps or services, aside from some auto suggestions. Even though Arc’s notes feature is very barebones, I still find it more useful than Apple’s Journal app.
Being able to add notes (or even longish diary entries) to specific visits in the timeline, then being able to search for them later, has proven to be super useful for me personally. Which is why I’d love to extend the notes feature a lot in future.
At one point the planned next app was even Arc Journal, a new app built specifically for that purpose. But life pressures made it not happen in the end. Maybe I’ll get another chance at it someday. But in the meantime, I’d still like to do a lot more with the existing notes feature too!