I would suggest studying traditionally i.e. from paper books. Human eyes are not made for long term exposure to screens. Eyes are made to intake light rays indirectly such as from paper, books, or whatever object you look at, but screens are a source of light just like bulbs, tubelight, sun etc, and this continuous exposure to light is bad for the eyes.
Believe me, i used to love the idea of studying magazines, books, novels etc on computer(lcd screen, not crt), but i started getting headaches due to computer eye strain syndrome. Nowadays i avoid all kinds of screens for as long as possible(even while typing this my eyes are closed for most of the time, as i can type without seeing easily).According to me, there are not many advantages of studying on tab, other than being portable and fancy.
While reading a book, you can underline or highlighten imp passages, fold pages for quick review, swap between distant pages easily, and i can remember pages due to photographic memory. Also there are a number of other advantages of books, i just can't point out all of them. so here are some links:
https://drhelen.blogspot.in/2010/12/kindle-vs-real-book.html
https://www.readwriteweb.com/archives/5_ways_that_paper_books_are_better_than_ebooks.php
https://the-billablog.blogspot.in/2011/09/why-books-are-better-than-kindle.html