To modify it and make it a bit more efficient, just little things, for instance going back to the annotation highlight to the list of notes i is possible from all the notes( pressing back) but not the notes in the specific book( pressing back in that case bring me to the home page)
I am not experienced with android and programming in general but I guess it would be just enough to set an activity intent..
And once I modify I would like to implement on my machine , is this possible if I am going to root it?
( are quite stupid questions, but why not? A curiosity is important to learn)