What does shake do on IOS Devices?

On the little assistive touch dot (on my IPhone 4) if you go to devices>more then there's a button that says shake, I have clicked on this multiple tunes but it doesn't seem to do anything. What does it actually do?

It shows one person dancing for a little while, then at one point flashes and shows everyone dancing, and wearing costumes.

Why the videos in my instagram don't open?
and what is the SHAKE button do in assistive shortcut?

  • Why would Apple make FaceTime only compatible with iOS devices? It doesn't make sense what if someone has an Android! Then FaceTime is useless to the person with the iPhone who wants to video chat with the person with the Android. Someone please tell me why Apple did this, I know it's a stupid question but its bugging me
  • Where can I watch One Piece on iOS devices? I need a website to watch One Piece dubbed in English on my iPhone/iPad. I need One Piece, no other anime and I'm only willing to watch the English dub, nothing else, please.
  • Reserve battery on iOS devices? A few years ago, one of my friends told me that you can access the extra 20 percent of battery from your iPhone, and he did it though MobileTerminal, does anyone know what to type (after getting into super user) and what to install in Cydia?
  • Is there an app for making Harlem Shake videos? What's a good iPhone app for editing Harlem Shake videos? I know there's iMovie but I'm looking for something that's preferably free and easier to use…