I have coded website for downloading mp3 from youtube video. Basicaly I am using APIs for MP3 and MP4 convertisons and everything works ok... Website is "youtubetake.com" and you don't need to visit it. While watching a youtube video enter "take" between "youtube" and ".com" to download MP3 Take a look at this animation. https://i.imgur.com/TrhGSLL.gif Website work at mobile phones. I made m.youtube.com version... Too. Where to promote this website? I think maybe it is better to promote it like - explaining to people how to use it. Something like "Youtube tips and tricks"....