the Splatt system

Now that I've come to actually making the splatt sytem ( as in the abilty to splatt your friends) I realised that I hadn't really thought about actual process of Splatting. Rather than having a simple touch the screen and splatt, I want something more interactive. I have two Ideas.

1. One would be a pull back (touch) sling shot so that you could aim and hit whre you want.
2. And the other is a power bar where you shake to fire tryig to hit the right mark. the coser you are the better the shot.