First of all, I would like to say I know that doing that goes against YouTube R&Rs but this app is just for educational purposes.
So far I have used YoutubeInMp3 API, but I found out that that API fails a lot by returning the website to download the video(HTML) instead of the JSON containing the link to download the .mp3 video. Apart that they restrict the download speed to a low one which causes lots of problems when playing it.
I am seeking for ideas on how to do it, using another API or a library.
Thank you in advanced!
PS: I would´t mind getting an answer in Objective-C, but I prefer Swift.