Three20 is an Objective-C library for iPhone developers

A native macOS KeePass client

Easy to use CFNetwork wrapper for HTTP requests, Objective-C, Mac OS X and iPhone

Cocos2d for iOS and OS X, built using Objective-C

Telegram Messenger for iOS

Experimental fork of Pieter's nice git GUI for OS X. Includes: sidebar, fetch, pull, push, add remote, merge, cherry-pick, rebase, clone, clone to. Mac OS X 10.5+ (see wiki for screenshot)

Serial port library for Objective-C and Swift macOS apps

Source List control for the Mac

Network Monitor

A collection of libraries such as OpenSSL, Cyrus SASL, OpenLDAP, and PCRE which have been ported to the iPhone/iOS platform.

HTML5 Plus for iOS

Switch OS X system proxy settings in menubar

calling any functions in any binary files under MacOSX

Code injection + payload communications for OSX (incl. sandboxed apps)