By algorithm I mean a scoring function to tell which video is relevant to the search.
Freetube but if you want HD you have to separate out the video and audio downloads then combine them after. A little annoying but it does have download right there in the client
freetube removed the download feature a while ago. see my other comment above on how i use freetube to download videos.
Dang really? Guess I just haven’t needed it in a while