A method is provided for calibrating an inertial sensing unit of a device utilizing a vision sensing unit integral to the device. The method includes receiving inertial sensing input data from the inertial sensing unit, receiving vision sensing input data from the vision unit, and determining when the received vision sensing input data represents a predetermined input state of the vision sensing unit. The method includes estimating an error value in the inertial sensing input data received from the inertial sensing unit based on the received vision sensing input data upon determination that the received vision sensing input data represents the predetermined vision sensing input state. The method further includes adjusting first subsequent received inertial sensing input data from the inertial sensing unit based on the estimated error value, thereby calibrating the inertial sensing unit.