@Hugh I have two main readers. I have a Kindle Fire tablet which I use sitting by a table or counter, and sometimes in my easy chair. If I'm going out and about I have a Kindle White Paper which fits easily in my pocket. I sometimes read off my phone but I do not like the little screen. If I read outside, I always use the White Paper. I find it easier to read than either a book or a tablet.
There are a couple of downsides with the tablet. One (my main problem) there are too many other things to read on it. I subscribe to the Atlantic and the Washington Post via the tablet, and my email is accessible from the tablet and I can get lost in my New York Times from there as well. (About a year ago, the New York Times stopped supporting the Kindle Fire through the app store, and now you click through via an email from them.) And since it is multi-functional I might get distracted by games or other apps as well. Two, it is not as heavy as a hard cover book, and it certainly more manageable in terms of losing your place etc. but it is noticeable that you have something in your hands (I have the 10 in. screen, quite large), much more so than the White Paper. If I could only have one reader it would be the tablet. But the weight and the outside ease of reading makes the White Paper a very handy device.