MBCommonMBCommon is a lightweight, generic Cocoa library for iOS and OS X.License: BSDObjective CMBRequestMBRequest is a simple, blocks-based networking library for iOS and OS X built on top of NSURLConnection and NSOperation.License: BSDObjective CMockDuckLicense: MITSCKitSCKit is a simple, unfocused Objective-C library. It is designed to contain useful code for both iOS and OS X projects. Currently, it has a definite iOS bias, but that may change in the future.License: BSDObjective C