純正
https://itunes.apple.com/jp/app/youtube/id544007664?mt=8
FoxTube
https://itunes.apple.com/jp/app/foxtube-youtube-cache/id486365960?mt=8
TubeBox Pro
https://itunes.apple.com/jp/app/tubebox-pro-amazing-youtube/id529391753?mt=8
McTube Pro
https://itunes.apple.com/jp/app/mctube-pro-client-for-youtube/id559638188?mt=8

前スレ
youtubeアプリスレpart2
http://hello.2ch.net/test/read.cgi/iPhone/1388187241/