Shimmer
An easy way to add a simple, shimmering effect to any view
...(To build the example locally, you'll need to open FBShimmering.xcworkpace rather than the .xcodeproj.) Shimmer uses the -[CALayer mask] property to enable shimmering, similar to what's described in John Harper's 2009 WWDC talk (unfortunately no longer online). Shimmer uses CoreAnimation's timing features to smoothly transition "on-beat" when starting and stopping the shimmer.