1. A method for determining an object sensing mode of a touch sensor panel, comprising: at an electronic device with one or more processors and memory, operating the touch sensor panel in a first object sensing mode having a first resolution, if a first touch or proximity event is detected in the first object sensing mode, switching the touch sensor panel to operate in a second object sensing mode having a second resolution, and if no second touch or proximity event is detected in the second object sensing mode, switching the touch sensor panel back to operate in the first object sensing mode.