I think this is the technique used by Philips in their app too: https://itunes.apple.com/gb/app/vital-signs-camera-philips/id474433446?mt=8 https://itunes.appl

I think this is the technique used by Philips in their app too: https://itunes.apple.com/gb/app/vital-signs-camera-philips/id474433446?mt=8 https://itunes.apple.com/gb/app/vital-signs-camera-philips/i... [iTunes link] What would be ideal is if the app also took your heart rate using a combination of both methods to reduce error, but I don't think either do this.