Microsoft employees commonly describe Windows 8 as having both a Render thread and UI thread.

Typically they say the Render thread performs animations and the UI thread handles most other operations: parsing, layout, applying templates, data binding, input processing, most app callbacks, etc.

Animations can be calculated from beginning to end when they are created. Sometimes the changes to the property being animated don’t affect rest of the objects in a scene. These are called independent animations and they are run on the composition thread instead of the UI thread. This guarantees that they remain smooth because the composition thread is updated at a consistent cadence…

Is this a common architecture or unique to Windows 8? What about Windows Phone 8? Android? iOS?