There are many products in the market for dyslexia kids or language learners, with which you can simply press the pen on top of texts, then the words or sentences get translated immediately on the screen of the pen. This kind of product is extremely popular in Asia. But none of them can support popular language learning apps like LingQ or Anki. They either can only translate words or sentence without any other functions (such as C-pen), or are only aiming Asian market and only supports syncing with their own apps. The manufacturing of this type of product is actually quite mature and mostly based on Android system, but only lack of better product design. Would be interesting that LingQ develop an application on top of that, like, bringing LingQ experiences to physical book reading. And when you want to review your vocabularies, you can still use the app to review it too.