Besides e-books, Schooltas also has a personal notebook. You can find it on the right edge of your screen by clicking the arrow:
Tap or click the "+" sign to add a new note.
You can add tags to indicate what the note is about. You can add hyperlinks and images to your notes. If you add a YouTube link, Schooltas will automatically embed the video.
Click "save" to save the note when you're done.