I read a few years ago that the biggest comics publisher in the USA was no longer DC or Marvel, it is a publisher who exclusively puts out manga comics. (I admit to not being sure why this is. While a classic like Akira was excellent, most manga seems same-ey to me. Admittedly my exposure to them has been limited.)
This idea was supported strongly by the wording in the user manual for the new Kindle Oasis: it is not called "comics" but "comics and manga". Huh. What happened to Batman?
Kindle Oasis by the way is very good, if you like e-paper screens/readers. It's well expensive though. (I think they should sell a version without the battery-cover, two weeks battery life is plenty.) But it pretty much is the "mini Kindle" I wrote about I wished they would put out, smaller and lighter. And they managed to do it with the same screen size, nice accomplishment.
Oh: for comic reading on a Kindle and smaller tablets, one pretty much has to use the Panel View feature. Which is why I don't like to read comics on anything less than a 10-inch tablet and preferably a 13-inch one. Because like Scott McCloud writes about in the famous book Understanding Comics, image juxtaposition is essential to comics. Take away the panels from each other, and it's no longer really a comic, it's a series of drawings.