libcrn is document image processing library written in C++11 for Linux, Windows, Mac OsX and Google Android. It is a toolbox that allows to create easily software such as OCRs and layout analysis tools.
Obsolete for most. Use the Ink2Text project instead - no Windows needed! A Linux/Unix library providing full cursive & printed handwriting recognition by connecting to a Windows XP Tablet back end. Need Service & client files.
Jarnal is a plattform-indepenent programm written in Java for notetaking, sketching and PDF-/picture-annotating. It works like a normal notepad with the difference of being digital. It is thought to be used with a stylus on tablet-pcs.