Gerhard Roth wrote various very interesting chess OCR applications that enable you to scan chess positions from books and open these directly in your favorite chess application for further analysis. Much faster than manually entering these positions through a position setup editor.
The application supports the Android sharing mechanism I blogged about a while back. For example, as illustrated below, first open a chess book at an interesting position, then invoke Gerhard's OCR application to scan the position, and finally select sharing to open, for instance, Chess for Android for further analysis with your favorite UCI or XBoard engine.
Chess for Android version 4.5 also introduced a fast way to invoke Gerhard's application. Long press the notation window, and the select Retrieve Position. This will bring you back in the OCR application again (or give you a choice if several such applications exist) to scan the next position. Great job Gerhard writing this nice Android application!