Here's a novel iPhone app that may be useful if you're evaluating a patient who has a tremor:
By DocCheck Medical Services GmbH
TremorCheck applies a clinically and scientifically proven method to measure and analyze human shaking, the so-called tremor. Measurements are made with the iPhone which has a very sensible 3-dimensional sensor measuring acceleration, recording the values of all three directions in space.
TremorCheck calculates a number of values from the measured data:
• Dominant frequencies in Hertz: Number of vibration of the hands per second
• Performance / strength in mWatt: The strength of the shaking
• Amplitude: The maximum deviation of the tremor
• Synchronization: "Steepness" of the peak of dominant frequency