Simulate a pinch or squeeze

I need some advice on how best to simulate a pinching or squeezing effect in Titanium mobile for iPhone/iPad. I'm looking to have a sphere or other object that will respond to a pinch gesture by squeezing, sort of like a stress ball.

Perhaps an image view animation with multiple frames of the squeezing effect dictated by the amount of pinch? I'm open to suggestions/examples. I'm new to Titanium/iPhone dev, though not to Javascript programming.

Thanks!

I think its possible by pressing alt/option key on the mac keyboard and then you'll see two dots on the simulator and can use mouse to do pinch or zoom.