API v2 deprecated. New youtube api v3 works only with developer token and has limitation for free connections.
You can get JSON without API:
http://www.youtube.com/oembed?url=http://www.youtube.com/watch?v=ojCkgU5XGdg&format=json Or xml
http://www.youtube.com/oembed?url=http://www.youtube.com/watch?v=ojCkgU5XGdg&format=xml
Thumbs:
Sometimes we want use thumbnails from video. But max picture size depends on video resolution (SD or HD). This information absent in json response. To detect picture max size without api you need get 200 response from sddefault.jpg.
http://img.youtube.com/vi/ojCkgU5XGdg/sddefault.jpg if 404 use hqdefault.jpg instead. It has less quality but always exist and you can avoid 1 requests for detection it .
http://img.youtube.com/vi/ojCkgU5XGdg/hqdefault.jpg Or use max size
https://i.ytimg.com/vi/ojCkgU5XGdg/maxresdefault.jpg Mini thumbs:
http://img.youtube.com/vi/ojCkgU5XGdg/0.jpg http://img.youtube.com/vi/ojCkgU5XGdg/1.jpg http://img.youtube.com/vi/ojCkgU5XGdg/2.jpg http://img.youtube.com/vi/ojCkgU5XGdg/3.jpg Annotations
http://www.youtube.com/annotations_invideo?cap_hist=1&video_id=ojCkgU5XGdg parse mobile page 16kb
https://m.youtube.com/watch?v=ojCkgU5XGdg don't forget change user agent to iOS / Safari 7
also
http://www.youtube.com/get_video_info?html5=1&video_id=ojCkgU5XGdg also how embed youtube live
https://www.youtube.com/embed/live_stream?channel=UCkA21M22vGK9GtAvq3DvSlA Where UCkA21M22vGK9GtAvq3DvSlA is your channel id. You can find it inside youtube account on "My Channel" link.
Live thumb
