Measure heart rate with Android phone? Seriously, can a smartphone do that? I stumbled on a free Android application ~ Instant Heart Rate by Azumio Inc. It turns your Android phone into a heart rate monitor. In short, it uses phone built-in camera to track color changes on the fingertip that are directly linked to your pulse. This is the very same technique that medical pulse oximeters use. Accurate or not? Try it out yourself to find out…