Never seen this before, just got a notification that 1Password 7 on iOS has an update…by Apple? To prepare for watchOS 27? The update date is shown as “Feb 1, 2023.” It all just seems a bit off so I’m holding off. Anyone have an idea what’s going on here?
And yes, I’m still using 1Password 7 
Sounds like phishing. I still use 1Pwd7 also - can’t run 8 (if I even wanted to). I haven’t seen any update notices on my iMac, MBP, iPhone, iPads or Watch.
It’s not phishing. Apple identified an issue with watchOS 27 that prevents some apps from running, so Apple is updating/patching the apps for developers so that they will run.
If the update is available in the App Store, then it is almost certainly legitimate.
I haven’t heard any news about hackers uploading app updates for someone else’s app. These kinds of fake-app attacks involve the attacker uploading a different app via a different Apple ID, which will not fool the App Store’s update system.
I see the update in the App Store on my iPhone. Still running 1Password 7 on my iPhone and iPad.
Interestingly, iMazing does not “see” this as an update because the version number did not change.
However, if you right click on the 1Password app and select Show Available Versions it does show two versions with the same version number.
I’ve run into this before, which is why I still also download updates using iTunes.