Yet another excuse for me to write my own e-reader friendly webapp

So many better e readers at that price point that also function as actual phones or tablets and run Android.

If it's for reading only, it's fine, but if you plan on doing a lot of writing and markup, skip it. The handwriting features are very limited, and you can't write on the actual pages or write margin notes at all, you can only write on virtual post-it notes that are kept separate from the book.

Yes every kindle since the very first one had an "experimental" web browser in various stages of usability. All currently supported kindles have a web browser that is fairly usable though very slow.

They have for years, but the browser was historically very stripped down and didn't get get certificate or SSL/TLS algorithm updates, leaving parts of the web inaccessible as time went on. I only ever use it to hit Project Gutenberg for public-domain ebooks (though their redesign a few years ago made that a lot harder)