Sparkle

is an easy-to-use software update framework for Cocoa developers.

• True self-updating--no work required from the user.

• Displays release notes to the user via WebKit.

• Displays a detailed progress window to the user.

• Supports authentication for installing in secure locations.

• Really, really easy to install.

• Uses appcasts for release information.

• The user can choose to automatically download and install all updates.

• Seamless integration—there's no mention of Sparkle; your icons and app name are used.

• Supports DSA signatures for ultra-secure updates.

• Sparkle requires no code in your app, so it's trivial to upgrade or remove the module.

New in Sparkle 1.5:

• Optionally sends user demographic information to the server when checking for updates.

• Dual-mode garbage collection support for any memory management style.

• Sparkle doesn't bug the user until second launch for better first impressions.

• Sparkle can install .pkg files for more complicated products.

• Supports bundles, preference panes, plugins, and other non-.app software.

• Supports branches due to minimum OS version requirements.

• Deep delegate support to make Sparkle work exactly as you need.

• Tons of other stuff! Read more about what's new.