Emacs manuals formats

I do not understand why, but for some weird reason none of the GNU manuals that I have been reading are available in ePub or anything like it. They're available as HTML in various forms and PDF. But some times you want to read it on your iPhone, iPad or a ebook reader like a Kindle. This have been something of a pain point for me for a long time. So I have tried countless different ways to deal with it. The only way I know about that works to do this on all of them, because of their size is the following: Download the PDF's Install Calibre Add the PDF's Convert them ot your device Send them to the device either over USB or for iOS devices you could add it from a Mac and sync it over iCloud.