4. The method of claim 1 wherein the application has numeric identifiers for respective application objects displayed thereby, and the application and passes the numeric identifier for one of the application objects to the manipulation API each time a received low-level touch input corresponds to the one of the application objects.
1. A method for interpreting low-level touch inputs into corresponding manipulation events, the method performed on a computing device having a touch-sensitive input surface and a display, the method comprising: receiving low-level touch inputs that correspond to touches of the touch-sensitive input surface, the low-level touch inputs comprising locations of contacts with the touch-sensitive input surface, the low-level touch inputs received by an application executing on the computing device; identifying, by the application, an application object, displayed on the display, to which the received low-level touch inputs apply; sending the received low-level touch inputs and information identifying the application object at a manipulation API (application programming interface), the manipulation API interpreting pluralities of the received low-level touch input as respective manipulation events, wherein the manipulation API is invocable by arbitrary applications on the computing device; receiving, at the application, the manipulation events, the manipulation events comprising affine transforms of the identified application object; and handling, by the application, the received manipulation events by displaying the application object according to the manipulation events.