Nexus 7 is powered with 1.3GHz quad-core processor and 1GB RAM. That performs faster enough to do something. Without a desktop computer and laptop, you can also directly edit the bulky videos on your Nexus 7.
AndroMedia Video Editor (echCat Mobile) is Android application which let you fully create featured video clips with special action effects, such as frame size, FadeIn and FadeOut, transition effects, HD export and overlay title clips. The app supports MP4, MOV, WAV file formats, and creates Frame size in 1280 x 720, 640 x 360 and 360 x 240. It's quite simple and easy to use on the tablet. Perfect for creating professional looking youtube videos.