I have been working on my own syncing framework for one of my Apps for quite a while. I explored many options along the way.

A very easy one which was comfortable to implement and quickly to work was the Dropbox Syncing API. Unfortunately, just when I finished adding it to my App Dropbox announced the discontinuation of this API due to low adoption from developers. Tough luck.

Since writing my own server-side backend was out of the question; it would take too much time and increase the maintenance cost of the App greatly. So I turned to Apple’s CloudKit, which was newly introduced about half a year earlier. While it was basically working fine, I came across some weird behavior that probably a bug, which hasn’t been fixed in the latest release of iOS 9.0 this year. So I decided to check out another solution I have came across: Ensembles

Ensembles is a syncing framework for CoreData, written by Drew McCormack, which even doesn’t need a server-side for syncing. A direct device-to-device sync is even possible. If you still would like to you a central point for exchanging the sync data, Ensembles isn’t married to any specific backend. Whether you want to build your own backend or use an existing one like Dropbox, or CloudKit – the choice is entirely to you. I am using Ensembles in a prerelease version of the upcoming Atsumeru 2 for over a month now and I haven’t been disappointed once.