A computer-implemented method for measuring a pulse pressure wave travelling through an artery using a pressure sensor of an array of pressure sensors which are mechanically coupled to the skin of a user proximate to the artery, comprising the actions of: using a computing device to perform the following process actions: employing one or more arterial location sensors to identify a location on the user's skin in the area proximate to the artery which exhibits the greatest displacement of the user's skin when a pulse pressure wave passes through the artery in said area, said action of employing comprising: employing the one or more arterial location sensors to measure the displacement of the user's skin when a pulse pressure wave passes through the underlying artery; and determining which pressure sensor of the array of pressure sensors that is closest to the identified location on the user's skin using the mapped locations of the pressure sensors, selecting the pressure sensor determined to be closest to the identified location; and measuring a pulse pressure wave travelling through the artery using the selected pressure sensor, characterized in that the action of employing further comprises: each arterial location sensor comprising an image-based arterial location sensor that has been calibrated so that pixels in the images captured by the image-based arterial location sensor are mapped to locations relative to each pressure sensor of the array; capturing images of the user's skin using the one or more arterial location sensors; and analyzing the captured images to visually identify the location of the greatest displacement of the user's skin when a pulse pressure wave passes through the artery. employing one or more arterial location sensors to identify a location on the user's skin in the area proximate to the artery which exhibits the greatest displacement of the user's skin when a pulse pressure wave passes through the artery in said area, said action of employing comprising: employing the one or more arterial location sensors to measure the displacement of the user's skin when a pulse pressure wave passes through the underlying artery; and determining which pressure sensor of the array of pressure sensors that is closest to the identified location on the user's skin using the mapped locations of the pressure sensors, selecting the pressure sensor determined to be closest to the identified location; and measuring a pulse pressure wave travelling through the artery using the selected pressure sensor, employing the one or more arterial location sensors to measure the displacement of the user's skin when a pulse pressure wave passes through the underlying artery; and determining which pressure sensor of the array of pressure sensors that is closest to the identified location on the user's skin using the mapped locations of the pressure sensors, selecting the pressure sensor determined to be closest to the identified location; and measuring a pulse pressure wave travelling through the artery using the selected pressure sensor, characterized in that the action of employing further comprises: each arterial location sensor comprising an image-based arterial location sensor that has been calibrated so that pixels in the images captured by the image-based arterial location sensor are mapped to locations relative to each pressure sensor of the array; capturing images of the user's skin using the one or more arterial location sensors; and analyzing the captured images to visually identify the location of the greatest displacement of the user's skin when a pulse pressure wave passes through the artery. each arterial location sensor comprising an image-based arterial location sensor that has been calibrated so that pixels in the images captured by the image-based arterial location sensor are mapped to locations relative to each pressure sensor of the array; capturing images of the user's skin using the one or more arterial location sensors; and analyzing the captured images to visually identify the location of the greatest displacement of the user's skin when a pulse pressure wave passes through the artery.