iOS open YouTube App with query (url schemes)
You can't use this http://www.youtube.com/results?search_query=foo
for opening youtube app. If you use the above url it'll open the safari instead of youtube app.
There are only three URLSchemes available for opening youtube app:
http://www.youtube.com/watch?v=VIDEO_IDENTIFIER
http://www.youtube.com/v/VIDEO_IDENTIFIER
youtube://
Reference: iPhoneURLScheme
this is working fine in iOS 9
youtube://www.youtube.com/channel/<channel-id>