Zephyr is multitasking gestures for the iPhone. To close an app, just swipe up from the bottom of the screen. To go to the previous app, just swipe in from the right. And to show the multitasking switcher, just pause for a moment while swiping up. No buttons required.
Zephyr is also extremely configurable. Directions, sensitivity, and almost everything else can be adjusted until your iPhone or iPod touch works just as you want it to.
Infinidock — Apps you love belong in your dock, but what if you use more than four? Infinidock lets you scroll your dock and add as many as you want.
Infiniboard — Why lock yourself in one dimension? Infiniboard gives the home screen two dimensions, letting icons be placed vertically and horizontally.
Infinifolders — Folders are cool, but 12 icons just isn't enough. Infinifolders makes your folders as big as you want them.
The iOS home screen is just page after page of the same icon grid. But does it have to be? Rather than always shifting your icons up and to the left, Gridlock puts you in control. With Gridlock, you can drag your icons and put them anywhere you want.
Find your apps faster and make each page easy to distinguish. Or, setup even the most complex themes without the mess of "blank icons" and without any extra effort.
ProSwitcher was the first user-friendly multitasking implementation for iOS, created by myself and Ryan Petrich. Extremely popular, with over a million installations, it was replaced by the official implementation in iOS 4. ProSwitcher is designed around webOS "cards", an easy to use model for multitasking, but is also extremely configurable.
VoiceActivator is the only way to customize Voice Control, and add new voice commands. Just type in a new command and setup an action, and it's ready to use right in Voice Control. It's fully integrated with Activator for launching apps or activating extensions, and also can easily open links or even read back the time and your battery percentage.
Paste is a simple, open source (BSD-licensed), client for pastie.org. When you open up Paste, your clipboard is ready to paste to pastie, or you can clear it and type something else. When you press submit, your paste will be submitted, and then contents of your clipboard will be replaced with the Pastie URL of your paste.
Private browsing features have spread like wildfire accross the desktop browsers. But what about the mobile space? Covert adds the feature to Mobile Safari itself, taking inspiration from Google Chrome. Covert is the best way to manage your privacy on the go. A similar feature was added by Apple in iOS 5.
A very popular feature of Mac OS X is the sound it makes when you press the volume up or down buttons. For an unkown reason, this noise is not present in iOS. MobileVolumeSound adds this feature back to iOS. It full supports all versions of iOS from 3.0 on, and hasn't needed an update since the initial release.