I'd say that compatibility appears to be random. I have used my old iPhone with unsupported software and it's been fine, then there are issues and so around it goes. You'll see on here that people with the same iOS version where one will be fine and the other with problems so severe that they go back to using a reader. I have settled on iOS 18.3 and had no problems. I can't upgrade the iOS because by the time Abbott confirm compliance the iOS version has moved on and iPhone doesn't allow you to upgrade to anything other than the latest version. I suspect at some stage I'll gamble an up date but not at the moment.
Abbott seem immune, or ignorant, of the criticisms of the situation. In response to my last email with them they said 'We do not have a specific timeframe for when new operating systems are going to be tested'. I guess that's true for all iOS developers, but I believe that Apple do have a test programme where they liaise with developers and I don't understand why Abbott cannot join that (I assume they haven't as they seem to be in the dark about the timetable for updates).
I can't understand why Abbott are wasting time checking compliance with an iOS version that is no longer available.
In their stock responses they tell users to check compatibility with their compatibility listing that is buried in their website. You'll need to check every day to try to beat the iOS update and I can't understand why Abbott can't create a database of people who have asked to be notified when a new compatibility list is published. They simply don't seem interested.
I think the freestyle product is great and has transformed users' understanding of their own blood glucose levels but the system is let done by flaky software. Yes, the reader is a viable alternative, but the system is promoted on the images of the use of a phone to monitor levels, albeit with a subtle disclaimer.
Sorry for the long post but I live in hope that someone at Abbott might read it and see things from a user's perspective.
Edited for typo