2xsai is a GPLd library for intelligent scaling of hand drawn pixel objects to double their original size. It is commonly used in emulators.
ACSLogo is an implementation of the Logo language, used in teaching programming techniques. The purpose of a Logo program is to move a 'turtle' around a canvas using commands.
(commercial) ActiveDeveloper is an incremental runtime Objective-C and C IDE, JIT compiler, and debugger for Cocoa and QuickTime. It features fast incremental Objective-C and C compilation, full native speed applications in deployment, and no ActiveDeveloper dependency in your products.
Adobe Source Libraries
The Adobe Source Libraries (ASL) are a collection of C++ libraries building foundation technology to allow the construction of commercial applications by assembling generic algorithms through declarative descriptions.
Appscript is a high-level, user-friendly MacPython to Apple event bridge that allows you to control scriptable Mac OS X applications using ordinary Python scripts. Appscript makes MacPython a serious alternative to Apple's own AppleScript language for automating your Mac.
ASbug-Reporter offers an easy way to prepare a thorough bug report to send to software developers, scripters, or others who are attempting to help troubleshoot a problem. Once the info has been entered, it can be transferred to the clipboard or saved to disk.
a kit to create a Set-up/Installation Assistant using the same User Interface than the one of the Apple Installer or Display Calibrator utility. It's made of a collection of Cocoa sources and resources that are available under a BSD License
AsteroidsQC is intended as a developer example, primarily using Quartz Composer as a game prototyping tool, and using Blender for the 3D sprites.
AutoGraf is an automatic class diagram (UML) generator for Objective-C. Generated diagrams are rendered using Quartz with transparency, suitable for presentations or print. On recent systems, class diagrams update automatically as you code...
Bellhop allows you to create and publish Mac OS X services using scripting languages such as Ruby, AppleScript, Python, Perl & F-Script. Each Bellhop document consists of a collection of services written in a high-level scripting language.
Berkeley UPC is a portable, high-performance Unified Parallel C compiler.
The BioCocoa framework provides developers with the opportunity to add support for reading and writing BEAST, Clustal, EMBL, Fasta, GCG-MSF, GDE, Hennig86, NCBI, NEXUS, NONA, PDB, Phylip, PIR, Plain/Raw, Swiss-Prot and TNT files by writing only three lines of code. The framework is written in Cocoa (Objective-C) and can be used in any GNUstep application that runs on Unix/Linux, Windows and Mac OS X and in any Cocoa application, intended for Mac OS X. The framework is licensed under the GNU-LGPL and is freely available.
(commercial) a BASIC game programming language featuring: function pointers, fully dynamic arrays, inheritance and polymorphism
Send selected plain or rich text?in the form of notes or short messages (SMS) ? to Bluetooth?compatible devices directly from your favorite Services-aware Cocoa or Carbon application with a single click.
The BSInspectors include a simple API for everyone to create his own plugins, so you can even inspect the objects you created just for your own projects.
CalcService calculates the results of selected formulas from within all Cocoa applications (such as TextEdit, Mail, iChat, Safari, and XCode)
CamelBones is a Cocoa/Perl bridge for Mac OS X. It allows easy access to the Cocoa API for Perl developers. It also allows easy, object-oriented access to an embedded Perl interpreter for Objective-C developers.
Carbon Errors provides a description of error codes.
The Computer Hardware Understanding Developer Tools (CHUD Tools) are designed to help hardware and software developers measure and optimize the performance of PowerPC Macintosh systems running their products under MacOS X
ClipDate is a free widget for Apple Mac OS X Tiger which generates the string of the current date and time on your clipboard. The format of the string is selectable.
CMCrashReporter is a free and open-source framework written in Cocoa which allow the user to easily send a crashlog back to the developer.
a simple Open Source (BSD license) app with source code that includes a class for parsing RSS feeds
CocoaDialog is an OS X application that allows the use of common GUI controls such as file selectors, text input, progress bars, yes/no confirmations and more with a command-line application. It requires no knowledge of Cocoa, and is ideal for use in shell and Perl scripts (or Ruby, or Python, or... etc).
Cocoatron is the suite of Automator Actions that brings drag-and-drop simplicity to creating and automating complex XML Processing Pipelines.
Code Collector lets you store code snippets with ease.
CoverStory allows you to easily view the code coverage of your unit tests.
CVS Set-Up Assistant
an assistant to help configure a CVS Server on Mac OS X
This application will setup a CVS repository on your machine, enable people to browse it via the web, allow developers to access it remotely (using ssh or cvs pserver), and announce the repository's existence to the local network via Rendezvous.
D frontend for GCC
GDC is a D language front end for the GNU Compiler Collection. It supports a number of targets and nearly all features of Digital Mars D.
Dabo is a 3-tier, cross-platform application development framework, written in Python atop the wxPython GUI toolkit. It has features that are critical for developing apps that need to access databases, such as data binding to controls, and database-independent SQL abstraction.
DeleteFork is an application for deleting file resource and data forks in batch. DeleteFork can also move resources from a data fork into the resource fork, then delete the data fork.
DrScheme is an interactive, integrated, graphical programming environment for the Scheme, MzScheme, and MrEd programming languages. DrScheme provides source highlighting for syntax and run-time errors, support for multiple language levels, an algebraic stepper, objects, modules, a GUI library, TCP/IP, Unicode, MysterX for COM support under Windows, and much more.
dSymbolizer decodes backtraces from stripped binaries if they have been build with the new DWARD/.dSYM format with a nice GUI.
easyPatch is a quick & simple patch maker for applications and projects.
eBook Library was developed to help you practice speed reading at speeds from 50 to 1500 words per minute using plain text Unicode (UTF-8) encoded files.
(commercial) an automated test tool for Mac OS X. Designed specifically for GUI testing, Eggplant combines image-capture-and-compare technology with a powerful scripting language that allows test teams to automate their repetitive tasks
EOGenerator is a command-line tool for generating Java and Objective-C EO classes from EOModel file(s) using a different method than Apple's EOModeler.
EOReporter is a command-line tool generate files (documentation, usually) based on information in an EOModel. Files can be generated on a per-entity, per-model, or per-model group basis. Some provided templates generate HTML documentation similar to the EOModeler list view. EOReporter is a direct descendant of the EOGenerator application.
a lightweight object-oriented interactive and scripting layer specifically designed for the Mac OS X object system (i.e. Cocoa). F-Script provides scripting and interactive access to Cocoa frameworks and custom Objective-C objects. It aims to be a useful and fun tool for both beginners and experts, allowing interactively exploring, testing and using Cocoa-based objects and frameworks
Flash'In'App is a Cocoa framework that lets you load and fully manage Adobe Flash movies from your own applications. It provides classes that play SWF files, communicate with them via External API, FSCommands, or Variables, control external resource loading, and much more. They can interact with Flash Player.plugin and SWF files themselves.
FSClass is a 'meta-class' that allows new classes to be created directly in F-Script programs, using F-Script code to implement methods, without adding any new keywords or syntax to the language
Game Networking Manager
a portable networking layer for REALbasic programs. Automatically connects to LAN clients, and allows direct IP connections. Event based structure allowing sending to all connections or to specifically connected users
The GenericToolbar package contains an Interface Builder palette and a set of classes to include in your project, most notably the NSCoding-compliant subclasses of NSToolbar and NSToolbarItem.
GMG Lablib is a Cocoa and OpenGL function library used for data acquistion, visual stimulation, and behavioral control on OS X.
Gradient Panel is a user interface for creating, editing and sharing gradients (colour ramps). Developers can incorporate the panel into their Cocoa applications easily and for free.
Green Dome GNUstepWeb for Mac OS X
Green Dome GNUstepWeb for Mac OS X provides a WebObjects 4.5-like environment for Mac OS X (with some support for WO5 additions). It is composed of modified versions of the standard GNUstepBaseAdditions, GDL2, and GNUstepWeb frameworks, built to run on top of Apple's Cocoa frameworks. The GNUstep frameworks have been built with Xcode as true Mac OS X frameworks.
Consider greenfoot as a combination between a framework for creating two-dimensional grid assignments in Java and an integrated development environment (class browser, editor, compiler, execution, etc.) suitable for novice programmers.
Growl is a cool tool for Mac OS X that provides notifications when an application needs your attention.
HelpbookCreator is an application for creating HTML-Helpbooks, which you can easily integrate in your with Xcode developed applications.