Jon Hocking recently released a simple category on NSDate that generates relative timestamps such as "3 hours ago" or "2 days ago" from an NSDate instance.
The code is available on GitHub at jonhocking/PrettyTimestamp and is available as a CocoaPod as well.
I’ve put together an example project to demo how the code works at stevenhuey/PrettyDates. It makes use of CocoaPods to manage dependencies so make sure to use the .xcworkspace file and run:
pod install
before trying to build and run the app.
When you save yourself some time generating some nice relative timestamps in your next app make sure give @jonhocking a mention on Twitter.