ios-realm-demo
This project aims at getting some kind of number in order to measure the performance of Realm.io vs Core Data. This is an extremely basic project measuring the amount of time it takes to insert a number of objects into both frameworks.
At the time of this writing, the benchmarks were approx. 101 seconds / 100k objects for Core Data and 196 seconds / 100k objects for Realm.
More testing is definitely needed but this is a first step.