Open Source Objective-C 2.0 Software for Linux

Midi Sheet Music is a free program that plays MIDI music files while highlighting the piano notes and sheet music notes. Works on Windows, Mac OS X, and Ubuntu Linux.

Synergy combines your desktop devices together in to one cohesive experience. It's software for sharing your mouse and keyboard between multiple computers on your desk. It works on Windows, Mac OS X and Linux.

RenderTools is an OpenGL based scenegraph library in C++ for Windows, OSX and IOS supporting OpenGL|ES1.1, ES2.0, OpenGL1.5 and up to the latest version (currently 4.2). It allows the developer to easily (de)serialize a scenegraph to-and-from xml, create renderbuffers, framebuffers, samplers, vertexbuffers etc. and cross-reference those items. RenderTools allows you to completely specify an application, its resources, viewcontrollers and its renderpasses in one single xml. GraphNodes such as RelationalNode, RenderNode, and TransformNode can be used to create a complex hierarchy for rendering. Both update and render calls can selectively include or exclude specific components such as geometric details or lighting or texturing.

DTDS is a system of definition of data types for unification of information exchange with use of different Samond Classes Library functions and for generation of source texts based on the completed data type definition

This framework provides basic components for acquiring, broadcasting, analyzing and storing the continuous geophysical data. Written on Objective-C and using GNUstep Foundation (Base) framework or Apple Foundation framework.

scl is Objective C library for macOS, iOS and GNUstep with custom set of ObjC classes and extentions of standard CF, Cocoa and Cocoa Toch classes, such as NSString

SimKit(because GameKit was taken) is designed to allow quick and easy cross platform abstraction away from platform dependant drawing and physics libraries. The APIs provide a generic way to make common calls for drawing, animating, and otherwise manipulating 3D entities, as well as shading and texture information.