Among the few disappointments that iOS 4.2 brought with it, AirPlay has been one users have been the most vocal about. In addition to being limited on which apps allow video streaming, the original Apple TV was left out of the party -- until now.

App Dynamic, the developers of the iOS-based Remote HD, announced this week that their original Apple TV plug-in has been updated with the newfound ability to do AirPlay video streaming from any iPhone, iPod touch or iPad with iOS 4.2 installed. The news was met with squeals of joy from orphaned first-generation Apple TV owners, who can now join the wireless streaming party.

So what can you do with AirPlay on the original ATV? Almost everything you can do on the second-generation black model, which includes streaming video from the iPod (on iPhone and iPod touch) or Videos (on the iPad) apps, as well as from YouTube. Pictures can also be streamed via the Photos app on any iOS device. If your iOS device is jailbroken, you can also stream video from most any third-party app. Unfortunately, at the moment audio-only streaming is not an option, but the developer claims this is coming soon.

Making the magic happen isn’t quite as easy as downloading an app -- your original Apple TV will have to be hacked, either manually or with the paid, user-friendly aTV Flash from FireCore, LLC which includes the Remote HD plug-in among its many feats of strength.

Here’s how to get rocking with AirPlay on your first-gen Apple TV, regardless of which method you decide to use. Note that in either case, you can’t really harm your original ATV, since you can always easily restore the device to stock firmware and be right back where Apple always intended you to be.

aTV Flash Makes It Easy

The easiest way to get AirPlay working on your original Apple TV is to purchase the $39.95 aTV Flash software for Mac or Windows. aTV Flash is essentially a user-friendly installer that brings together a host of open-source software from various developers, including nitoTV (which allows you to play additional codecs on the ATV, including DVD disc images), Couch Surfer Pro (think Safari on your television), Last.fm streaming, FTP and SSH access, XBMC and/or Boxee and yes, Remote HD.

Remote HD is a universal iOS app which lets your handset or iPad double as a remote control, but also offers sophisticated VNC capabilities for compatible devices. The company makes a small server software package for Mac and Windows to allow your computer to be used anywhere you have an Internet connection with the Remote HD app, as well as a plug-in for the original Apple TV to get the same functionality.

aTV Flash has an extensive PDF available documenting how to install the software on your white Apple TV, so we won’t repeat all of that information here. The short version is that you’ll install the required components onto a USB thumb drive from your Mac or Windows computer, unplug the power cable from your Apple TV and then plug the aTV Flash thumb drive into the ATV’s USB port. Power up the ATV and you’ll see an aTV Flash logo at startup, followed by a long list of Linux jargon as the software does its thing. When prompted, power off the ATV, remove the flash drive and power the ATV back up again.

Once your hacked ATV fires up again, you’ll now see a couple of new menu options, including nitoTV and Maintenance -- the latter is where you’ll go to install the Remote HD plug-in, which should be version 4.2.8 in order to enable AirPlay streaming. Although the software doesn’t force you to buy the Remote HD iOS app, they’re technically a package, so be sure to head to the iOS App Store and pick up Remote HD while it’s on sale for only $3.99 -- you won’t be sorry.

If you already own the Remote HD app and have your white Apple TV hacked using aTV Flash, the good news is you’re just a click away from enabling AirPlay -- simply head to the Maintenance menu, select Install Extras and scroll down to the Remote HD plug-in option, which should now list “Update” next to it. Run the update, restart the Finder and your Apple TV should now appear as an option from the AirPlay menu on your iOS 4.2-equipped device.

Install Remote HD Directly on a Stock ATV

If you don’t need all of the goodness that aTV Flash offers or don’t want to spend $39.95 for the ease of installation, you can opt for doing it yourself using free open-source tools and the Remote HD software.

First, you’ll want to follow the instructions to install atvusb-creator in order to hack your original Apple TV. The process is similar to getting aTV Flash installed, however the software is a little less user-friendly. Your Apple TV should already be at version 3.0 or newer -- if it’s not, you’ll want to upgrade first for a smooth experience.

With your ATV unlocked and connected to your local network via either Wi-Fi or Ethernet, you’ll now use the Terminal software supplied with Mac OS X to connect to the box and install Remote HD. Head to your Applications folder, then open Utilities and double-click Terminal to run the app. After a moment, copy and paste the following command into Terminal:

ssh frontrow@appletv.local

Now you’ll be asked for your password, which is simply “frontrow” (no quotation marks). You’ll be connected to your white ATV and can now issue three separate commands into Terminal which will download, uncompress and finally install the Remote HD plug-in. Be sure to hit the Return key after each one!

scp ssh.remotehd.com:RemoteHelper.tar RemoteHelper.tar

tar xvf RemoteHelper.tar

./install-RemoteHelper

If you happen to get a password request, just type in “frontrow” once more, again without the quotation marks.

After the Remote HD plug-in installs, your Apple TV will restart and you’re ready to go. Open the Remote HD app on your iOS device and after a moment you should see your ATV box appear under the first section, “Computers around you.” Tap on the “AppleTV” selection and the app will connect to the box and you’ll be able to navigate your ATV remotely from the app. Note that the default password is empty, but you can always select one of your own for extra security.

Last but not least, you can open an AirPlay-compatible app, start playing a video and then tap the AirPlay button -- you should now see “AppleTV” as one of your video streaming options. Select it, and in a moment your video will be magically thrown directly to your orphaned white Apple TV box, all without wires.

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