I saw this post by @astropixie about how it’d be nice to review fics on AO3 as you read. A little while back, because I was so in awe of the Clexa fic writers, I made this userscript (can install on Firefox by using Greasemonkey and on Chrome by using Tampermonkey) so that I could do just that. It doesn’t have the wattpad or soundcloud functionality, it’s just a little thing added on to a page, not something supported by the site itself, but it’s better than nothing.
The userscript is available here: http://pastebin.com/vYBCYWu4