Expected behaviour is an important aspect of software design. iTunes has often been criticised for having a sync system that’s opaque and too readily insistent on deleting data. Apple’s dialog boxes rarely help, providing warnings that are indecipherable, even to people who’ve written about the company for years.

One of the biggest criticisms about iOS has been the manner in which apps are removed from a device during a sync if they’re no longer in iTunes, which of course takes app data with it. “Boom,” as Steve Jobs would have once said. However, this action through to iTunes 10 did at least provide the means to ‘rescue’ such apps, with the dialog box pictured below. The text within notes that purchased items are on a device, but not present in the iTunes Library. You get two options: Transfer copies the items back to iTunes; Don’t Transfer deletes them from the device.

Curiously, iTunes 11 leaves the dialog box in place but also does not—with my hardware—perform the Don’t Transfer action. Space is seemingly made on the device, ready for deleting various apps, but the deletion then does not occur. I’ve no idea if this is a bug or intentional. In a sense, having iTunes now work like this could be a good thing—less chance of accidentally removing an app through having deleted it in iTunes. The dialog box, though, suggests it’s another bug—one of many I’ve found in iTunes 11 now I’ve been using it for a while. From a personal standpoint, I’d quite like Don’t Transfer working again, because I used it for app management—it’s much faster to remove a few dozen apps from a device by deleting them from iTunes and doing a sync than by zapping them one at a time on the iOS device itself.

Update: As of iTunes 11.0.1, I’m finding that this dialog box no longer appears. It looks like the bug here was therefore the dialog box and not the syncing, and the app-removal feature has itself been removed. As per the article, I’m in two minds about this: for me, this will make app management harder, but for the general punter, it doesn’t really make sense to remove an app from a device if it’s not in the iTunes library on their PC or Mac. Also, it looks like the system has some intelligence—when I was playing around with it earlier today, it transfers to the computer updated apps that are in the library but not apps that aren’t.