https://www.engadget.com/2013-01-08-ces-2013-ispo2-pulse-oximeter-for-idevices.html
CES 2013: iSpO2 pulse oximeter for iDevices
Jan 9, 2013 - Masimo makes medical-grade pulse oximeters, which measure the amount of oxygen in your blood. Now available (for US$249) is the iSpO2, a more consumer-grade...
pulse oximeterces