I've recently moved from Android to iOS, again. I wanted to share my current experiences.
Over the years I've posted several times about managing photos from a smartphone. The last time I was using iOS, I used Air Transfer to move photos from the iPhone. I fully expected to use it again this time but I haven't.
First I'm going to share my workflow and then speak to the nuances.
At the end of each day, I launch Google Photos and wait until the icon at the top right has a green check-mark.
Then I visit my iOS Camera Roll. I select and delete all the photos that I don't want to archive, e.g. screenshots, receipts, etc. Remember that they really aren't deleted, just moved to the Trash folder for 30 days.
Then I launch the OneDrive app and wait until it says "Up to date". Here (archive.is) is Microsoft's instructions on how to setup OneDrive for Camera Roll. Make sure to turn on "Include Videos".
UTC. Still that is better than using a timestamp of when the file was transferred.
Two side issues: 1) You may want to turn off auto-replication of OneDrive's Camera Roll folder. Otherwise all the pictures will get copied to all of your instances of OneDrive. 2) You also may want to turn off HEIF so you get only JPG. You can do this on the iPhone by going to Settings / Camera / Formats / Most Compatible. Or you could add HEIF support to Windows.
Then I go back to the iOS Camera Roll and select and delete all the photos. You may not want to do this.
The non-Apple apps tend to not run passively in the background even if you enable Background App Refresh.
I've got a couple of more topics to cover: MapMyWalk, Maps, and battery usage.