Systems and methods use a mobile device to position an annotation of displayed content on a shared display coupled with a host device. Sensor data, such as gyroscope and accelerometer data, from the mobile device may be transmitted to the host device and used to generate the annotation. The sensor data may be preprocessed to smooth and fit the data to a parametric curve or shape prior to or after display on the shared display. The user of the mobile device may interact with the mobile device to further start and stop the annotation, as well as denote to animate the annotation.