There were several responses to my ebooks blog post, so I will share them here. Thanks all!

Certainly the current formats of ebooks are not suitable for mathematical content: apart from some horrible debacles with completely unreadable formulas on kindle (and other) ebook readers (on hugely expensive ebooks), it is not just the problem of properly displaying readable formulas and diagrams. Mathematics book have an important 3dimensional nature, where one continuously needs to jump back and forth between a lot of different points in the book: something extremely easy to do with a print copy and an impossible nightmare on an ebook that is designed to linearly read a novel from first to last page. I don’t think print format will have a better replacement soon for mathematical content. That said, I personally often accompany the print copy I have of a book with a simple (and cheap) PDF file that is searchable, so I can search on the file and then I read and work back and forth on the paper copy.

I like e books. Being an old guy, the backlighting, high contrast, and ability to adjust the type size are important to me. It is helpful if the reader allows one to page quickly back and forth through the text. Being able to print a few pages at a time would also be a big help. I don’t see the need for video widgetry in advanced texts.

I do read math books in electronic format sometimes, but always as pdf or djvu on my ipad and not on my kindle. I agree with Matilde that none of this quite reproduces the high dimensional experience of reading a physical book, but the ipad is so much closer than the kindle. But I don’t know how singular this is to math books as opposed to academic reading more generally. Certainly I have heard many horrified and disdainful conversations about kindles and ebooks among English professors.
But unless mathematicians stop travelling so much, ebooks are a part of our present and our future. I don’t have the talent for it, but I hope someone who does designs a better math ebook. I imagine a revolution of reading mathematics of roughly the same order as TeX was a revolution for the writing of it. I can’t imagine specifics, but I hope it comes soon.

I agree with Matilde that the current ebook technology still cannot compare with an actual book, for the reasons listed; at the same time ebooks have changed our lives for the better since we’re no longer limited to what we can carry on our backs when traveling.
It is my hope that future ebooks will be available which allow one to easily keep notes and switch backand forth. I also think computerlike screens aren’t good for reading; what we need is something kindlelike but 4 times larger area wise (it’s no use being able to enlarge the character if then you have to squint at one quarter of the commutative diagram at a time).As for interaction, I think we’ll move to being able to add notes and put them online, so that people who are confused (something that happens to me a lot!) can click and see what others have to say. This is something I found useful already as a student, when the same effect was achieved by pencil remarks on the margin of the library copy.
I also think that David Fisher’s comparison with TeX is true in another important sense: mathematicians use books like no one else. If we want a system which is tailored to our needs, we will have to build it ourselves. I think the AMS and its sisters societies can play a very important role in this.

i have been working for two years on how to make a math ebook that is readable, since, as you note, kindle math books aren’t really working.
i’ve come up with an approach that i think works. the good news is that it takes full advantage of the color space, form factor, and dynamics possible on a phone/tablet. the bad news is that it’s not compiled, and requires a lot of finedetail manual positioning. also, it took a year just to get the fonts right, and they are as yet far from perfect.
i’m 1200+ pages into this project, resulting in three ebooks on multivariable calculus. you can see the latest entry here at the kindle store & use the “look inside feature”. but, really, it looks so much crisper on a good phone.
https://www.amazon.com/CalculusBLUEMultivariableIntegralsPrimaryebook/dp/B01IGRPCXI/
rob ghrist, math, upenn
ps: i’ve talked with folks at amazon about how to adapt the kindle platform more to the needs of math ebooks. they were polite, but not really ready to move into that space yet from what i can tell.
Curtis McMullen says:
September 10, 2016 at 7:26 pm (Edit)
Ebooks can be very useful to undergraduate students. I am currently teaching a course on “Sets, Groups and Knots”, and there was homework during “shopping period”, while students were still deciding which courses to take. Ebooks allowed them both to get an idea of the course and to do the first reading and homework without having to buy the books.