A system for providing metronome therapy for a user by selecting an audio file from a plurality of stored audio files each having predefined beat parameters using motion data from a mobile computing device connected to or held by a user, the system comprises: at least one mobile computing device having motion sensors, wherein the motion sensors are operable to detect deceleration of motion of the user; means for setting a sensitivity level for the motion sensors such that the motion sensors are operable to detect cadence of movement of the user when the user is stepping; means for obtaining motion data from the motion sensors; and characterized by a sensitivity bar operable to adjust the sensitivity level of the motion sensors depending upon said cadence of movement by calibrating the motion sensors to detect steps of a user according to said cadence of movement; means for using the motion sensors to detect deceleration in said cadence of movement of the user, means for comparing the detected deceleration to a predetermined range and if the detected deceleration falls within the predetermined range of decelerations that are attributable to Parkinson's disease the system is operable to generate and record motion data relating to the detected deceleration; means for computing from the motion data step data based on a number of steps taken by a user in a specific period of time; means for computing an individually prescribed metronome beat for the user by applying a multiplication factor to the step data and generating a metronome beat file from the individually prescribed metronome beat; means for automatically selecting a stored audio file having a predefined beat parameter matching the metronome beat of the metronome beat file, and audio output means for providing the metronome therapy to the user by playing the audio file so that the audio file is heard by the user. at least one mobile computing device having motion sensors, wherein the motion sensors are operable to detect deceleration of motion of the user; means for setting a sensitivity level for the motion sensors such that the motion sensors are operable to detect cadence of movement of the user when the user is stepping; means for obtaining motion data from the motion sensors; and characterized by a sensitivity bar operable to adjust the sensitivity level of the motion sensors depending upon said cadence of movement by calibrating the motion sensors to detect steps of a user according to said cadence of movement; means for using the motion sensors to detect deceleration in said cadence of movement of the user, means for comparing the detected deceleration to a predetermined range and if the detected deceleration falls within the predetermined range of decelerations that are attributable to Parkinson's disease the system is operable to generate and record motion data relating to the detected deceleration; means for computing from the motion data step data based on a number of steps taken by a user in a specific period of time; means for computing an individually prescribed metronome beat for the user by applying a multiplication factor to the step data and generating a metronome beat file from the individually prescribed metronome beat; means for automatically selecting a stored audio file having a predefined beat parameter matching the metronome beat of the metronome beat file, and audio output means for providing the metronome therapy to the user by playing the audio file so that the audio file is heard by the user.