For some developers, iCloud is clearly broken

Wondering why some of your favourite iOS apps have yet to support iCloud sync? Many developers are voicing out their frustrations to give us a clearer picture. 

“I’ve rewritten my iCloud code several times now in the hopes of finding a working solution,” wrote developer Michael Göbel in a blog post, and “Apple clearly hasn’t.” The problem is this: Apple has failed to improve the way it syncs databases (“Core Data”) with iCloud, yet has continued to advertise and market iCloud as a hassle-free solution.

There are a number of technologies under the iCloud umbrella. Turns out that if an app is using the Core Data technology, then iCloud sync will have unpredictable behaviour that could cause data loss. If the app is using the document-based sync technology, then iCloud sync will be far reliable. To make matter worst, it is not easy for an app using Core Data to switch to use document-base sync. Doing so amounts to the work of rewriting the entire app.

Even Apple’s own Trailers app, which uses Core Data sync, fails to keep track of user Favorites due to data loss. And we can only speculate why Podcasts app just added iCloud sync with the latest version released last Thursday.

Apparently these stability issues with Core Data iCloud sync dates back to iOS 5. And Apple has been quite about it. Although Core Data iCloud sync has improved in iOS 6, but reliability issues remains. And there is no promise if Apple will solve the bugs with the upcoming iOS 7.

With its Maps fiasco and developers unhappiness, there is lots of room for Apple to improve on its software and cloud offering. The worst nightmare for Apple will happen when the most polished apps appear on Android first.