iphone/ipad - started going to the library again though nothing beats an actual book!!!
I don't usually buy books on iphone/ipad mostly frees, some are really good especially crime ones, although haven't looked recently! only times ive paid are when they're addictive series like "the facebook killer"! and i did buy fifty shades series as everywhere was sold out and wanted to know what the fuss was about lol.
I have a kindle paperwhite, and I use it quite a lot to read ebooks that my dad has bought....but if I need to buy a new books for myself I like to buy a physical copy, though I'm not too sure why. Kindle books are cheaper and take up no space!
I usually read on kindle or iBooks on my phone, means I can read in the dark at night, the majority of books I now listen to on audible, I started because of the amount of driving I did, now I listen when cooking, getting ready etc, I get through over 80hrs a month, much more than if I tried to read the normal way
Paper books, because I can pick up some decent ones for mere pennies at the local bookshop. I've tried to get into Kindles and the like, but there's something magical about discovering a book in a second hand bookshop.
I have an old style kindle. Which I love for when I am on the busses. I also have the kindle app on my phone and tablet. Have the kobo app too, but most of my reading is through kindle. I still like proper books though too.