I never really used Siri much before. But recently I bought a book on Amazon that was written by a friend. Normally I do not carve out time to read these days and prefer to stick my Air Pods in and just listen to the book with audible.com. This works well for me on novels but not technical stuff. But my friend's book was not available on audible so after a bit of playing around and getting nowhere with text to speech aps I found that the siri feature can work. Text to speech aps works for many documents but not for books that run from the cloud or encrypted books you download to your iphone. So, in the general settings you can find Accessibility and turn on Screen Speech. Now open your Kindle e reader app and find your book. Open the first page. To activate the speech reader, use two fingers pulling down from the top and a player will overlay and the Siri voice will begin reading. You can control the speed and go forward and backward pause and play. The kindle app will advance the page when Siri gets to the bottom. Not as good as audible but now I can have audible convenience to listen to great books while other activities occupy my eyes. Works for emails and other documents as well. Although I did not see this feature reference Siri, the voice in the screen speech feature is the same. That's why I called it Siri. It's really a hidden iOS feature I never knew existed.