The iPad and Mac need to be on the same Wi-Fi network for Air Display to work, naturally. The app and companion System Preference on the Mac (below) work so well together that I had no issues watching YouTube videos that were playing on the Mac on my little "side screen." They looked great on the iPad, although it was disconcerting to hear the sound coming out of the Mac.
One really great feature of Air Display is that not only is it an additional screen for your Mac, but it also adds a second input device to your Mac. I was able to use my finger on the iPad to call up incoming email that was appearing on my virtual screen. I didn't find the accuracy of finger input to be very good in this pre-release version, though, and ended up resorting to a Pogo Stylus for better input accuracy.
There were a few bugs in Air Display, which isn't surprising considering that it's still in beta. When I first started streaming a virtual Mac screen to my iPad, I noticed that the connection kept dropping. A look at the AirPort status in the iPad status bar indicated that the Wi-Fi signal strength had dropped to about one bar, much less than the five bars I see on my network. I rebooted the iPad and everything worked fine after that.
There were also some interesting screen artifacts that sometimes showed up while using Air Display. Once again, they didn't keep me from using the second display, but they just looked a bit odd. Avatron spokesman Elliot Chase mentioned that the artifacting issue and dropped connection issues have been resolved in preparation for release.
who has been working on Air Display at Avatron, noted that after three months of development Avatron is pretty comfortable with how the app is working right now. He mentioned that he's "really proud of it,", that "it keeps pace with playing YouTube-sized videos just fine," and "the only pain points for screen updates are full window moves" that they're working on.
Avatron hopes to submit Air Display to Apple for approval next week, with an expected price of US$9.99.