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.