From the video , it looks like it works pretty great (the app won't be available until 2015 though, the year true future stuff happens according to BTTF). PhotoMath explains:
"PhotoMath reads and solves mathematical expressions by using the camera of your mobile device in real time. It makes math easy and simple by educating users how to solve math problems."
It’s an application that scans an equation on paper by using your smartphone’s camera, and then proceeds to solve it instantly. Not only do you get your answer right away, you get a step-by-step breakdown of the solution. Still, if you’re curious about it, you can sign up to be notified when it’s ready for download.
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