What is TubeMate?
Allows to download videos for offline viewing to the sdcard of the device. Google controversially remove all YouTube downloaders from Google Play (Android Market), but it is available at other Android markets such as SAM - SlideME Application Manager . This app is not Open-source and contains advertising, but it is free.
Comments and Reviews
Said about TubeMate as an alternative
A no nonsense one click downloader
it's user friendly, supports many languages, has active development team support