Gitbook. I've used it for two small (unpublished) books. https://www.gitbook.com/ https://www.gitbook.com/ E: I may have misparsed your question, upon re-rea

Gitbook. I've used it for two small (unpublished) books. https://www.gitbook.com/ https://www.gitbook.com/ E: I may have misparsed your question, upon re-reading it and had an overly liberal understanding of "solicit feedback". Apologies in advance if my answer isn't quite up the alley you were looking for.