The new litmus test for apps: How well does it AirPlay?

The first thing I do when people ask me to show them how to use their new Apple TV (s aapl) is to mirror the screen of my iPhone 4S to their device. It’s guaranteed to impress, especially if your audience is unaware the tiny black box could do that. You can see gears turning as people think about the implications of that capability combined with the apps they already use and love. And that’s why AirPlay should be a focal point for developers from here on out.

Hedging bets in case of an Apple television

That’s something Revolution Studios co-founder Tony Warriner suggested could be a good idea for game devs in an interview on Wednesday with Warriner said that AirPlay is “worth doing now, because as we all know, a big TV play from Apple is just around the corner,” even though for now it’s “like the big forgotten iOS feature” in many game developers’ minds.

Warriner’s suggestion for game developers to bake in AirPlay features now is mostly about future-proofing products. But even if an Apple TV set takes a long time to come to market, there is plenty of cause to use AirPlay now, for game developers and makers of any and all iOS apps, regardless of their niche or focus.

Apple TV’s shifting role

The current Apple TV is basically a great Netflix (s nflx) box for most users, which now also has the added advantage of being a full-featured audio and video streaming device for your mobile phone or tablet for just $99 (or $89 now, at Best Buy (s bby) and Amazon(s amzn)). But in the near future, the Apple TV could see a role switch, with the expanded content of the entire App Store displacing the Netflix appeal as a No. 1 reason for owning and using the Apple set-top device.

The increased flexibility allowed by AirPlay Mirroring on Apple’s latest iPhone and iPad means that developers should start thinking about AirPlay not as an afterthought or preventative measure against future obsolescence but as a value-add competitive advantage that can help their product stand out from the growing crowd that is the App Store.

Go beyond the bare minimum

AirPlay compatibility isn’t just about allowing your content to be displayed on a TV when thrown from one device to another. It’s about making sure there’s a unique experience that only AirPlay users can access. Note that this also doesn’t mean taking anything away from the app itself as a standalone mobile product, just that users who can take advantage of the benefits of owning the Apple TV do have something more to make use of.

For some developers, providing a value-add AirPlay experience could be as simple as deciding to include a video or slide show alongside an article that can be thrown to the screen instead of providing text-based content alone or making sure it works in landscape orientation so it looks better on a TV. But more-ambitious (and therefore more-standout) examples could provide supplemental information or additional screens with hands-on demonstrations displayed back on the originating device while AirPlay video or slide shows appear on the TV screen. It’s definitely possible, as Real Racing 2 HD’s dual-screen gameplay mechanism demonstrates.

One more reason to buy

The bottom line is that if I’m looking at a video-focused app right now, I’ll try to find out how well it handles AirPlay. If it doesn’t, or if the experience is less than ideal, I’ll pass and try to find another. Soon, if any two apps are relatively close in terms of features and function but one offers a tailored AirPlay experience while the other doesn’t, it could become a crucial factor in a buying decision. The Apple TV isn’t yet a barn burner in terms of sales, but lower prices should help. It is still ranked No. 1 in Amazon’s Digital Media Devices sales charts and No. 2 in Television and Video.

Plus, AirPlay will only come to more devices as Apple goes about its regular update cycle, and it could even come to the Mac. In an ecosystem where discoverability can be a problem and marketing advantages are few and far between, real AirPlay innovation and dual-screen interfaces are the next frontier, and I can’t wait to see some pioneering developers stake their claim.