Titanium - animation is v. v. choppy - titanium

Question

So i have an image that i want to drop down the page.
Should the user click a button, the image will stop said dropping down the page.
I've used the eventListener 'complete' style to execute this... and it works, in a fashion. The problem is that the dropping down is choppy ~ irritatingly so.
Is there a more efficient way for titanium to do some form of simple animation?
Here is a code slice:
ballAnimation = Ti.UI.createAnimation({
top: ballDown.top + 0.01*heightOfScreen,
duration: someSpeedHere
}, function(){
if (hasBeenPressed){
return;
}
else if (!hasBeenPressed && ballAnimation.top > lowestPointForBall){
someFunctionHere(); //this isn't part of the problem.
}
}
);
ballAnimation.addEventListener('complete', function(){
if (hasBeenPressed){
return;
}
else if (!hasBeenPressed && ballAnimation.top > lowestPointForBall){
someFunctionHere(); //this isn't part of the problem.
} else {
ballAnimation.top = ballAnimation.top + 0.01*heightOfScreen;
ballDown.animate(ballAnimation);
}
});
ballDown.animate(ballAnimation);

Answer 1

For animations it is advised to use a 2D matrix with a translation like this:
var translation = Titanium.UI.create2DMatrix(), deltaX, deltaY; // set the deltaX and deltaY according
translation = translation.translate(deltaX, deltaY);
ballDown.animate({
transform : translation,
duration : someSpeedHere
});