How to Make an iPad Expandable
Instructions
1Expand your storage capacity through an SD card adapter connected to the dock connection. The interface is designed so that photographers can view their images on the iPad, so all the files on the SD card must be accessed through the iPhoto app, which can display both photos and videos. Plug the adapter into the connector on the bottom of the iPad and then insert the SD card into the adapter. Note that you can also use a USB adapter to connect to a memory card reader to perform the same function.
2
Add input options to your iPad through Bluetooth accessories. You can use an external keyboard, mouse, speakers or headset through the integrated Bluetooth radio. Pair the device to your iPad and you can use it for input and output beyond what the iPad had built in. For example, if you write a lot on your iPad, the on-screen keyboard may be cumbersome. Using a Bluetooth-connected keyboard will allow you to write more comfortably, especially when paired with an iPad dock that holds the screen up at an angle for easy viewing while typing.
3
Amplify your output capability through the use of a Video adapter or Audio and Video adapter. Depending on the inputs for your home entertainment system, you might use the High Definition Multimedia Interface adapter, which carries both sound and picture, or you might use a VGA monitor cable to connect to a computer screen. If you use a separate video adapter, you can plug the 3.5 mm headphone jack on your iPad into external speakers or, with another adapter, into a home stereo system.
Source...