Arkadiusz Holko with a very clever technique for making motion animations look much more realistic. I actually used a very similar technique to this in one of our older apps where I included a motion blurred transition image but Arkadiusz goes into detail on doing this dynamically.
The Apple reachability code is some of my least favourite code to include in a project (and I guess the feeling inside Apple is mutual as it's never made it into any of the frameworks). Jared Sinclair has taken a crack at cleaning it up and adding some block based handlers for network status changes.
Class prefixes (in Objective-C) clearly make sense for library code, but I have never subscribed to the viewpoint that app specific classes needed to also be prefixed. I always justified it to myself by thinking of the app namespace as the "un-prefixed namespace" 😬. Brent Simmons speculates that maybe it's Swift which has caused the removal of the "Class Prefix" text field in the latest beta of Xcode.