Several partners have been asking us about the options around getting access to media streams as they come and go from an iOS device. While more robust media access features are further off, I wanted to take some time to explore the options an iOS developer can play with today.

The UIKit view hierarchy integrates with a fairly simple animation and compositing API. Every instance of UIView is backed by an animation layer (CALayer), which can be accessed (and manipulated) without much complexity. A neat thing about CALayer is that you render its contents at any time using the renderInContext: method. Most often, your render target is the window, which is managed by the UIKit view hierarchy, so none of this knowledge is particularly compelling. Unless of course, you wanted to render the contents of the animation layer to a bitmap in memory to perform, say, facial recognition with the iOS 5 CIDetector.