Legalities of downloading videos from YouTube [closed]

Question

I was asked by my boss to incorporate "downloading form youtube" into my android app, while I have tried to explain to him that it is illegal, he repeatedly claimed that he has done it before, and by logging into some account, youtube provides the registered user api to download stream video(for apple user, possibly) , anyone knows of any legal document that I can use to prove that downloading from youtube is illegal? or is there really a legal way to do so? Thanks

Answer 1

http://www.youtube.com/static?gl=GB&template=terms&hl=en

you agree not to access Content or any reason other than your personal, non-commercial use solely as intended through and permitted by the normal functionality of the Service, and solely for Streaming. "Streaming" means a contemporaneous digital transmission of the material by YouTube via the Internet to a user operated Internet enabled device in such a manner that the data is intended for real-time viewing and not intended to be downloaded (either permanently or temporarily), copied, stored, or redistributed by the user.