By Bulldozer Software
Open the Mac App Store to buy and download apps.
Decelerator allows you to customize the acceleration setting of your mouse or trackpad. While System Preferences can change the tracking speed, it doesn't actually allow you to modify the factory default acceleration setting. There are a number of reasons you might want to do this:
1. Gamers often disable mouse acceleration entirely to gain a competitive edge in "twitch" reflexes. With mouse acceleration off, a distance on-screen corresponds with an exact distance your hand must move, and is unaffected by the speed with which it moves there.
2. Windows users often find Mac OS X's relatively high mouse acceleration disorienting and frustrating. Lowering the mouse acceleration can go a long way to easing the transition to a new operating system.
3. Some people prefer higher or lower acceleration settings for many reasons both logical and illogical. If you're one of those people, then Decelerator allows you to tweak to your heart's content.
Decelerator costs $1 (and no, I don't believe in reminding you how that compares to a cup of coffee, though I guess I just did!), with 70 cents of each purchase going to the "feed a starving developer" fund. I've been using the app very happily for the last few months, and I hope it's as useful (in fully unproductive ways!) for you as it has been for me. If you have any comments or suggestions, I'd love to hear them on the forums at http://www.bulldozersoftware.com/decelerator.
One more thing. I hate it when developers charge upgrade fees to users, so new Decelerator versions will ALWAYS be free for existing users.
Ok, two more things. If you have a problem, please please please contact me instead of (or at least in addition to) submitting a bad review. Developers have no way of contacting reviewers for details, and since I am unfortunately confined to only 5 senses, I can't actually fix "Horrible aplication I ever bought". I tried to address the 3 negative reviews so far here: http://www.bulldozersoftware.com/x/blog/2011-07-18-decelerator-gets-3-bad-reviews
* First public release!
So I bought and tried it on Mountain Lion.
All it does is it lowers the tracking speed. Had it at 90%, disabled acceleration in Decelerate, went to System Preferences to find out it was lowered at about 40%. And if you then try to increase it, OS X will override this app and guess what: you're back to square 1.
$1 isn't much, but if you make an app claiming to have some functionality, then please make sure it actually works. Sorry to say, but at the moment, at least for ML users, this app should be removed from the App Store.
Waste of time
It says that it will make the mouse move more like Windows, but it just makes move faster and more chaotic. The developer didn't understand that increasing the speed doesn't mean decelerating.