By Anya Kamenetz

It sees you when youre sleeping … it knows when youre awake … it knows if youve been hitting the books, so be good for goodness sake!

No, its not Santa Claus. Its the digital Jiminy Cricket each of us carries in our pocket, otherwise known as a smartphone.

In a small experiment, researchers at Dartmouth College have shown that data automatically collected by an Android app can guess how students are spending their time — predicting their end-of-term grades with scary accuracy.

How did they do this? And what does it mean?

via The Quantified Student: An App That Predicts GPA : NPR Ed : NPR.