Awesome app for previewing app icons directly on your device. Easy, seamless integration with your Mac: drag and drop an image to the menubar icon, and, bam, it's on the device. The Mac companion app is free and can be found on the Mac App Store here.
The only caveat is that you can only preview one icon at a time. I ==really== hope they will add the possibility to add several icons (grid or even scroll based) so you can be able to compare several iterations at once.
Damn, this is pretty nice. Add particle effects to UIKit, just like in Cocos2D: create them with UIEffectDesigner, then add them to your project with UIEffectDesignerView. Works for both iOS and Mac. Still in beta, but I haven't found any glitches so far.
So what if you didn't pay attention in Geometry class--this is the real world, and in the real world, you have CGGeometry.h
Know it well, and you'll be on your way to discovering great new user interfaces in your apps. Do good enough of a job with that, and you may run into the greatest arithmetic problem of all: adding up all of the money you'll make with your awesome new app. Mathematical!
Today I found this great block-based UIAlertView, by Warren Moore. You can customize pretty much everything, except textAttributes for each button type separately. I forked it, modified it and also added a customizable, random angle for the (included) fall animation when dismissed.
Among other things, it supports landscape ==and== rotation from one orientation to another (some classes I stumbled upon 'till now supported both orientations as well, but not the rotation from one to another; silly, I know).
I issued a pull request, so until it gets approved (if it ever does) you can find the tweaked version on my GitHub.