I use iMazing, but today the update to iOS 18 did not go well, so I won't do updates with it anymore. The problem lies with that little component that your computer needs (Finder and iMazing both lack it, at first). iMazing was not able to load that component (it said, I need the component. Should I download it? [yes] I pressed Yes, nothing happened, and my iPhone 15 was stuck at the beginning of the progress bar + Apple logo.
First workaround: take iPhone 15 from its case so the button presses can work faster, and press Up quickly, Down quickly, and hold Wake button for 10 seconds. Then the phone was in Recovery Mode. But iMazing still wanted that component and then didn't do anything when I told it to go ahead and download-install it.
iMazing grabs devices before Finder can get them, so the iPhone in Recovery Mode wouldn't show up in Finder.
Second workaround: set iMazing Mini NOT to load on boot, and then of course don't open iMazing. When you reboot, Finder will be able to show iPhone under Devices. Once that was achieved, Finder asked to download that component (why wasn't it included in yesterday's macOS Sonoma 14.7 update?) and we were home free on the upgrade.
This is why iMazing is not good for major iOS updates: You have to get that special little component to load in Finder, and that requires that you first try to update an iOS device in Finder. If the update doesn't require a little component, there's no difference between iMazing and Finder. But if you need the component (and you won't know until it's too late), only Finder seems to be able to install it. Once Finder installs it, additional updates are fine in iMazing. The little component—I think, but I'm really not sure—only happens at a major iOS update. It happens—again, my guess—when the iOS has a major update, but the macOS is still on the previous (or any previous) version. So, when I tried to get iOS 18 but am running Sonoma instead of Sequoia, I need a little shim, as it were. I needed to get that shim/component on my MacBook when Apple Chat Support recommended I try another computer today. The little MB2015 running Big Sur actually almost was able to update my iPhone to iOS 18!! It might have worked if we'd been sufficiently patient.
My strategy going forward: I will use iMazing for retrieving data from my phone (videos from my dashcam, Messages for archiving, etc.) and backing up devices. But for updates, especially major ones, I will back up in iMazing, then tell the device to update itself over the air.
I too am old school and never liked the idea of updating (an OS!?!) over the air. However the only way to update iOS/iPadOS with Finder is to reboot with iMazing Mini set not to Launch on boot. Otherwise, iMazing grabs devices away from Finder. In that case, over the air might be easier. But I'll probably turn off iMazing (launch iMMini on boot: 'off') and reboot so I can use Finder.
