Apple says it's fixed a bug that's been causing some apps downloaded from its store to crash as soon as they're launched.
The problem was first highlighted by Instapaper creator Marco Arment after he was deluged with emails from disgruntled customers, but affects dozens of other apps too.
"While in theory Apple's servers must be ready to distribute the new app binary by the time they start sending update notifications to users' devices, something goes wrong inside Apple's distribution servers, and customers receive a damaged binary instead of the good one that we've sent to Apple," explains Good.iWare.
"The exact reason is up to Apple to determine, but it looks like some binary encryption that happens internally in the App Store is only halfway-done at this point, and customers receive incorrectly (or partially?) encrypted binaries to their iPads. Those binaries do not get recognized by iOS as valid App Store executable binaries, and iOS simply refuses to launch them."
Arment warned users: "If this happens to you, all of your most active users, the people who will install updates within hours of them becoming available, will be stopped in their tracks. They’ll think you’re careless, incompetent, and sloppy for issuing a release that doesn’t work. And they’ll leave you a lot of angry 1-star reviews."
In a series of statements, Apple's said that it's been working on the issue - which it puts down to a single server that generated DRM code for some apps being downloaded - and believes it's now fixed.
The company says that only a small number of users were affected, and that they should now be able to download their apps again without any problems.
As predicted by Arment, though, many apps are now showing unfairly poor review ratings. And given that the problem's taken two days to resolve, many developers aren't too happy.