(Above: iPad screen to the left, and MacBook Unibody on the right.)
Note: iPhone 3G Camera Sucks.
Let's get this part out of the way: If you have an Apple laptop that supports extended desktop and an iPad and are looking for a second display, you should download Air Display. It's $10, but it's completely worth it.
Air Display is an App that converts your iPad into a second screen for your computer over wifi. It works best for those who sometimes need the extra screen real estate for instant message windows or an extra browser window.
Here at iSmashPhone, one of the best uses we've found already is to run it along side a MacBook and read news off of the iPad screen while having our text editors open in another browser window. It's also extremely useful for having a Twitter feed run in the background without taking up precious space on your laptop screen.
It's very simple to get the App running. You download it from the App Store, then you point your computer's browser to the developer's website and download their software. After that you open up the settings on your Mac and start the App on your iPad. You can arrange the displays in your computer's system preferences to set them to your liking. You will also probably want some way to prop your iPad onto so that it can stand upright next to your laptop's screen. (We've got you covered there, too)
There is a downside, but it's minor. Because the display is shared over wifi, there is a small amount of lag when dragging windows (the lag is not very noticeable when you are only moving the cursor). Which is why this works best things such as IM windows or twitter feeds. One practical example would be if you are a Photoshop user and decide to use the iPad as a second display, it may serve best as a space to put your tools and layer windows while your main display houses your canvas. Another would be if typing a report. You would probably want your word processor in your main screen while you have the page you are gathering information from on the iPad.
It's more than worth the price of admission for those who don't already have a second screen and want the extra space. It's great for those who often need to have a second tab open in the background and would like something more efficient than switching back and forth between tabs. Of course, if you already have an extra monitor, or your computer doesn't support an extended desktop, this App is not for you.
-Effectively makes your iPad into a second display
-Best App of its kind currently available
-Only supports Snow Leopard
4.5 out of 5