Generally you can't download youtube video from mobile but i will tell you the trick by which you can download youtube videos from mobile... Step:1 -1'st go to the your browser ( Opera & UC Browser are best browsers for mobile ) and go to the site youtube.com . Step:2 - Search the video which you want to download.. Step:3 - You will see the address of video in adress bar. Step:4 - If you had opened the mobile site then you will see the adress like- m.youtube.com/xyz.... . and if you opened the full site you will see adress like- www.youtube.com/xyz..... Step:5 - Go in adress bar and edit, in place of m.yout... .or www.yout... . you write ssyoutube.com/xyz Step:6 - You will see a new site with details and downloading option in the left side of site. From here you can download either in mp4 or 3gp format .... Enjoy downloading.....