Air2Files Server lets you access your Mac files on your iOS device. The server app, which is installed on your Mac, lets you share a folder. Then, you can use Air2Files on an iOS device to access the files inside that folder. If the file type is supported by the iOS device, you can even play it. For this app to work, both the client and the server should be connected to the same wireless network. Files can be accessed on-the-fly, or you can copy the files to your iOS device for offline viewing. Some of the supported formats are DOC, XLS, PDF, MP3 and MP4.
There isn't much that you can do on the Mac side of the application. In fact, the Preferences window only shows the folder that you want to share. The Menubar icon allows you to access the Preferences window, the about window and to quit the application. There are also links to other applications by this developer.
In conclusion, Air2files seems like a nice tool to have, especially if you want to use your iOS device to transport files or to play video files stored on your Mac while on-the-go. There isn't much support from the developer.