Below you’ll find some of the more prominent open source iPhone applications available for free download on the Web. The iPhone is brimming with paid apps, but with the advent of the Google Android platform and the surge of free and open source apps that it promises, we’re now starting to see a much welcome growth in iPhone open source projects. I’ll keep this listed updated as and when I find new software. If you have a suggestion to add to the list, please leave a comment and I’ll include asap. Enjoy!

Molecules

Molecules is an application for the iPhone and iPod touch that allows you to view three-dimensional renderings of molecules and manipulate them using your fingers. You can rotate the molecules by moving your finger across the display, zoom in or out by using two-finger pinch gestures, or pan the molecule by moving two fingers across the screen at once.
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WordPress for iPhone

The WordPress for iPhone app lets you write posts, upload photos, edit pages, and manage comments on your blog from your iPhone or iPod Touch. With support for both WordPress.com and self-hosted WordPress (2.5.1 or higher), users of all experience levels can get going in seconds.
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TubeStatus

TubeStatus allows you to get up to the minute service details on all London Underground tube lines in a quick and easy to use format. It also includes detailed line messages as provided by Transport for London (TFL).
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Tris

Tris is a Tetris clone game for iPhone. The project was intended as an example of general programming practices within the iPhone frameworks and of attractive interface and effective interaction design for the iPhone platform.
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hp Calculator Emulator

This app emulates the popular hp scientific calculators. Get complex mathematic power straight from your iPhone.
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Mobile Terminal

Mobile Terminal is a terminal emulator application for the iPhone. It does not function as an SSH client, nor Telnet, but it can be used to execute a console ssh-client application.
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App Sales Mobile

App Sales Mobile allows iPhone developers to download and analyze their daily and weekly sales reports from iTunes Connect. The newest reports can be downloaded with a single tap and all numbers are automatically converted to your (selectable) local currency. With clear bar charts you’ll get a quick daily overview of how your apps are doing in the store.
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Gorillas

Gorillas is a turn based single player and multi player game where the objective is to blast your opponent away using carefully aimed bananas.
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Twitterfon

TwitterFon is a simple, clean, easy to use, and super fast Twitter client for iPhone and iPod Touch
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iPhone Books

Books.app is a simple eBook reader for the iPhone. It reads HTML and text files stored in your ~/Media/EBooks folder, and is smart enough to enter subdirectories, if for instance, you’ve broken a book down by chapters.
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Open Clip

OpenClip is a non-profit, open-source, community-effort project, which promotes a framework for the iPhone that allows users to copy / paste between participating applications.
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