This is not a question but I thought I'd let anyone know who's having problems with playing YouTube videos from within an app. I spent half a day trying to sort it out before I came across this:
http://stackoverflow.com/questions/19604684/youtube-player-for-android-crashes-on-ads-playback
A bug has been raised with Google but nobody knows when it will be fixed.
http://stackoverflow.com/questions/19604684/youtube-player-for-android-crashes-on-ads-playback
A bug has been raised with Google but nobody knows when it will be fixed.