AirPlay is probably one of the most underutilized features in Apple products. It allows users to wirelessly stream photos, music, or video directly from their iPad, iPhone, iPod touch or Mac to their Apple TV or AirPlay-supported speakers. The Apple support page has a complete list of all the supported and needed devices. Mirroring is also available, but only for the iPhone 4S, iPhone 5, and iPad 2, all of which need to be running iOS 5 or later.
So, if you don't feel like shelling out $99 for an Apple TV, here are a pair of apps you can download instead, so you can stream content from your iPad, iPhone or iPod touch directly to your networked Mac.
AirPlayer costs $4.99 and takes advantage of pre-installed Apple software. Bonjour, a zero configuration-networking program that allows for devices and services to connect to a network automatically, is duped into thinking that an Apple TV is connected somewhere in the local network. Once that fake connection is established, you can now stream your content to any other Apple device, just like Apple TV. If you have your MacBook hooked up to your TV, you can take full advantage of the app.
Banana TV, which was created by Erica Sadun, creator of AirPlayer, is basically an older version of AirPlayer. It only supports iOS 4.2 through 5.0. So, if you have an older device or simply haven't updated in a while and want to save 5 bucks, then this your best bet.
There are other options, like Air Video, so which one is your favorite?