UniFi Drive 4.0 with photo backup, at least at the time of writing (March 22, 2026) is completely useless unless you keep the app open at all times. For most people, this is not acceptable. This system relies on the UniFi Endpoint app and personal drives, but if enabled, you must keep the app foregrounded to backup photos. They do say it is “automatic” but it is not automatic.
(Tested over the period of time since the app was released until today, it never worked automatically.)
iOS 26.1 added PhotoKit so at some point, hopefully it becomes more useful.