A device (120) for processing data for a wearable apparatus (100, 110), the device (120) comprising an input unit (122) adapted to receive input data, means (124, 116, 117) for generating information, referred to as wearing information (WI), which is based on sensor information and indicates a state, referred to as wearing state, in which the wearable apparatus (100) is worn, and a processing unit (121) adapted to process the input data on the basis of the wearing information (WI), thereby generating output data.