4. The computer-implemented means of claim 3 , wherein the one or more interactions includes at least one of: applications opened, inputs typed, gesture patterns used on a touch screen, body motions, eye movements, voice input, accelerometer sensor data, and gyroscopic sensor data.
5. The computer-implemented means of claim 4 , wherein learning the function mapping from the inputs to the brain health metric further comprises using at least one of: global positioning coordinate data, an outgoing phone call number and duration, an outgoing email address and length, an outgoing text message number and length, an incoming phone call number and duration, an incoming email address and length, and an incoming text message number and length.