Analysing data collected on our mobile phones could give insights into our health.
Up to 10 million people around the world are living with Parkinson's disease, which causes symptoms such as a shuffling walk and tremor in the hands.
But researchers in the UK hope that a phone app, which records a patient's movement and voice patterns, could help their doctor to monitor their progress more accurately.
The app includes seven different tests - for tremor, walking gait, reaction times and voice.
Dr Fahd Baig, clinical researcher at the Oxford Parkinson's Disease Centre, says that there are tell-tale signs in the voice of a Parkinson's patient.
Results from one of his pilot studies indicate that simply getting a patient to say "ahhh" into a phone means the app can spot this with 99% sensitivity.
For more information visit the BBC News website