Free iPhone app Discover isn’t as polished a solution to hosting, sharing, and transfering files to and from your iPhone as Air Sharing, but for casual use, it’s hard to beat the free price.

As most new iPhone/touch owners find out, usually in a disappointing revelation, their devices are the only Apple portables that don’t offer a “disk mode” for easy, thumb-drive-like file carrying and transfer. Apps like Discover (and Air Sharing) create a temporary webDAV network share, allowing Windows, Mac, or Linux systems to connect by adding the iPhone’s IP address as a network drive or, in the case of Discover, using a browser to access the app’s web-based interface.

Also supported is Apple MobileMe syncing/transfer and a connection to an OS X-based server as well.

Discovery is a free download for iPhones and iPod touch models running the 2.0 or later software; the paid ($5) version that’s available takes away ads.