When you are not at home or you are traveling a lot, what is your preferred device for learning/reading?
Laptops are obviously the most powerful and have the biggest screen but are also somewhat heavy to carry around.
Tablets are less powerful, have smaller screen but are easier to carry around.
Smartphones are usually the least powerful, have the smallest screen but are also the easiest to carry around.
I prefer using a tablet since it's rather easy to carry and the screen size is just about right.