Pen that does not make mistakes?

Surely many will rejoice at this new invention, which corrects our mistakes, if we make any such accident.
New project in Kickstarter showed packed with electronics pen that vibrates every time you make a mistake in the spelling of a word. According to the invention, their creators will make learning more enjoyable and rewarding.
The device is called Lernstift (from German: pen learning). It vibrated not only when we make a mistake, and when our handwriting becomes too cramped.

Source: http://bg-daily-news.eu