Sparkle

Sparkle is an easy-to-use software update framework for Cocoa developers.But this Little framework`s got a lot of features packed inside! Check `em out: New in Sparkle 1.5: Optionally sends user demographic information to the server when checking for updates. Supports bundles, preference panes, plugins, and other non-.app software. Dual-mode garbage collection support for any memory management style. Supports branches due to minimum OS version requirements. Sparkle doesn`t bug the user until second launch for better first impressions. Deep DeleGate support to make Sparkle work exactly as you need. Sparkle can install .pkg files for more complicated products.