1. A method, performed by computing functionality, for providing a user interface experience in response to vehicle state, comprising: receiving inference-input information from one or more input sources, at least one input source comprising at least one movement-sensing device, provided by a mobile device, for sensing movement of the mobile device, the mobile device operating in a vehicle mode when used in a vehicle and a handheld mode when used outside the vehicle; inferring a vehicle state of the vehicle based on the inference-input information; and presenting a user interface experience to a user who is operating the vehicle in response to the vehicle state, the user interface experience imposing attention-related demands on the user, where the attention-related demands are selected based on the vehicle state that has been inferred.