Physically-based loading indicator

While working on the appFigures iPhone app we experimented with several replacements for the standard iOS loading indicator (mainly for technical reasons, but also esthetics). We built this physically-based loading indicator using Facebook POP.

It acts like a spinning wheel with a natural decay that gets ramped up occasionally. We quite liked how the variable spinning speed makes it feel like it's working extra hard every now and then. It's familiar yet different, and the code-based solution ensures it'll be unique each time.