Seems to do what it says

I am a RT and if you think that a phone app is going to be as accurate as a pulse oximetry that is your own fault. This app gets with in 2-4% of my oxygen saturations. My heart rate usually seems pretty close as I have compared it taking a physical heart rate. It does what it says it will do. If you want something accurate go spend the $30+ dollars.

JIMSSAD about Pulse Oximeter - Heart Rate and Oxygen Monitor App, v2.2.5