On iCloud Syncing

February 07, 2013

If you follow the Cocoa development community you probably know how big of an issue iCloud syncing is. Watching the WWDC videos from last year you might think iCloud is the next big thing in Cocoa, much like Bindings or Core Data. It’s only when you start really looking at it in depth that you realize just how many bugs and edge cases you have to account for. Trying to enable Core Data iCloud syncing is a huge undertaking for advanced developers, and even the more reliable document and key value store syncing can have its share of problems.

More and more developers have started down the iCloud path and realized too late what the actual issues are. Some have updated their apps to remove iCloud support, and others are not even shipping until Apple fixes some of the problems they’ve run into. I’m definitely part of this crowd with some of my apps I had hoped to ship last year. I started with Core Data before I decided it wasn’t worth the risk and moved my app to document based data storage. Even now I’m not sure I’m on the right track though. My app has a very simple data model, but even after putting in a good amount of work and re-writing things two or three times there’s still work to do.

There are other solutions, including open-source sync frameworks like TICoreDataSync, and Dropbox’s new Sync API. Some of these look quite promising, but in the end it’s impossible for any third party library to achieve the same simplicity and support iCloud promises. I’m hoping Apple realizes just how many developers are affected and is working to improve things. It’s clear that this is hurting the Mac OS and iOS software ecosystem, and if even if some of the problems are resolved it will be hard getting developers to trust iCloud when there are so many horror stories out there.

Marc Charbonneau is a mobile software engineer in Portland, OR. Want to reply to this article? Get in touch on Twitter @mbcharbonneau.