If you're on OS X and writing your app with Cocoa, Carbon, or RealBasic, just use the Sparkle framework. You just have to maintain a RSS feed with the updates;

If you're on OS X and writing your app with Cocoa, Carbon, or RealBasic, just use the Sparkle framework. You just have to maintain a RSS feed with the updates; it'll automatically check for updates, show the user the release notes to see if he wants the update, download it, verify the signature, install the update, and restart the app. It's simple to integrate with your app, too. Dozens of apps like Adium, Vienna, and TextMate use it. http://sparkle.andymatuschak.org/ http://sparkle.andymatuschak.org/