After graduation, I went back to reading for fun and felt reticent about writing in my fiction books with no paper to write ...

If you prefer reading e-books, most e-readers and apps offer built-in annotation tools. These tools allow you to highlight text, add notes, and even export your annotations for further analysis.

That's why the Onyx Boox Note Air4 C, a $500 digital notebook and annotation tool, offered an alluring alternative: Mark up e ...