Make your Ipad a second screen
You can easily and cheaply add a second monitor to your Windows or Macintosh computer… if you already own an iPad or iPhone. Several ex-Apple engineers have created Duet Display, a $15.99 app that adds a second display for your Mac or Windows computer. It works well for any task that you might want to leave running all the time while dedicating the bigger screen for other tasks. For instance, you might want to keep a window open on the iPad or iPhone to monitor incoming email messages while using the main screen of the computer for word processing, surfing the web, or playing games. In fact, you can do all of those things simultaneously: run several programs on the big screen but still keep one program, such as email, displayed on the iPad or iPhone’s screen. The second display can be added to desktop and laptop computers alike.

DuetDisplay
Several other apps are available that loosely perform the same function over wi-fi which leads to slow and somewhat “jerky” video on the iPad or iPhone’s display. The difference with Duet Display is that it sends the video at high speed over your present charging cable, resulting in immediate display of the video on the mobile device’s screen.
Duet Display works with both the newer Lightning cables as well as the older 30-pin Apple cables. Another benefit of Duet Display’s application is that the cable is simultaneously recharging your iPad or iPhone, helping to keep it charged all the time.
Duet Display requires installation of two pieces of software: the Duet Display software for the iPad and iPhone is available from the App Store for $15.99. A small, free piece of software for the Windows or Macintosh computer also must be downloaded from the Duet Display web site and installed.
The video below shows the Duet Display in operation.
You can learn more at http://www.duetdisplay.com