Apple Digital AV Adapter review

Apple’s new $39 Digital AV Adapter gives HD-capable iOS devices a feature they have sorely lacked: the ability to output HD video. At last, those HD videos on your iPad, iPhone 4 ( ), or fourth-generation (4G) iPod touch ( ) can be displayed as they were intended—on a big, beautiful HDTV.

The small white adapter has a male 30-pin dock cable on one side and, on the other side, an HDMI port and a dock connector port. Connect your device’s AC adapter to the wall (or dock cable to your computer) and plug it into the adapter, and you’ll be able to keep its battery up even if you’re watching Lawrence of Arabia. But using that port is optional—if all you do is plug one end of an HDMI cable into the adapter and the other into your TV, and press play on your device’s Videos app, you’ll still get HD video and Dolby Digital 5.1-channel surround sound through a single cable.

There are some caveats. Though the adapter supports 1080p resolution output with the iPad 2 (720p for the original iPad, iPhone 4, and 4G iPod touch) the iPad doesn’t actually support playback of 1080p video content. The maximum video resolution supported is still 1280 by 720 (720p) at 30 frames per second (which is what all HD content is in the iTunes Store, for example). And according to Apple’s specs, movie playback is limited to 720p in any case.

I suspect that the advanced graphics power of the iPad 2 actually makes it capable of playing back 1080p video, but Apple’s video player hasn’t been updated to support such files. Certainly, storage is a concern for mobile devices with limited capacity—a 1080p sample video I tried (and failed) to sync to the iPad 2 took up twice the space per minute as a 720p video—but it’s a shame the iOS doesn’t yet support 1080p playback, regardless.

I played back several HD video files on several different HDTVs using the iPad 2 and the AV Adapter, and the video quality was excellent. It’s the same story on the iPhone 4 and the original iPad: my 720p test video (2009’s Star Trek movie) looked great. The inability to output HD video has been a sore spot on the iOS since the release of the original iPad—it was one of my complaints about the iPhone 4, in fact—but now that it’s here, it looks (and sounds) great.

The Digital AV Adapter provides iPad 2 users with yet another feature, one exclusive to the new version of Apple’s tablet: When connected to the HDMI adapter, the iPad 2 displays a duplicate (mirrored) version of the contents of its screen on an external display. Want to demo an education app for a classroom full of kids via a projector or HDTV? The iPad 2 makes it possible.

In mirroring mode, the iPad’s interface is crystal clear. It looks great. Because the iPad’s video interface is a 4:3 aspect ratio, you’ll find black bars on the sides of the TV when in mirroring mode. The bars grow even wider if you put the iPad in portrait orientation, but the image from an iPad 2 in portrait mode still looks good—albeit smaller—on an HDTV.

On a few TVs I tried, however, I needed to adjust the video settings in order to display the entire picture. (On the LG TV in my office, I needed to change the preset from “16:9” to “Just Scan.” On a Vizio TV at home, I had to manually change the video offsets.) It depends on how your TV set frames HD content; my advice is to fiddle with the video settings until you get a picture that pleases you.

For the record, the iPad 2’s mirroring mode and its video-out mode don’t fight with each other. If an app supports direct video output to an external display, the iPad stops mirroring and switches to that mode. In addition to the Video app, there are lots of other examples: Keynote uses the external display as a presentation screen while the iPad screen contains notes and preview information; Netflix and MLB At Bat let you control the interface on the touchscreen while the video plays on an external display.

My biggest complaint about the Apple Digital AV Adapter is that it took so long for it to arrive. Now that it’s here, it can turn any 2010- or 2011-era iOS device into an HD video powerhouse. It may be a little strange to see a gorgeous HD movie playing back from a tiny little iPhone 4, but you know what? It’s a good kind of strange.

Macworld’s buying advice

If you have an iPad, an iPhone 4, or a fourth-generation iPod touch, Apple’s Digital AV Adapter finally makes it possible to output HD video (with audio) from your iOS device to your HDTV. If you travel frequently, give presentations, or just like to share what’s on your iOS device with others, it’s a great addition to your bag of tricks. And the ability to optionally power your device at the same time gives it the flexibility that no other Apple video cable provides.