A decade ago, I had a Game Boy Advance SP. For this GBA SP I had an accessory which was pure magic at the time, an adapter that allowed for RCA video input to the device. Being able to plug in things like my GameCube or my VHS player (which also meant TV) to a 240 x 160 pixel 2.9-inch display was nothing short of pure awesomeness back then, and I still remember sessions of playing Pokemon Colosseum on the GBA’s screen while watching video on my state-of-the-art 14-inch CRT TV. The GBA was eventually replaced with a portable DVD player, which also had this ability. Heck, the same adapter that came with the thing to allow for video output could be used for video input by flipping a switch. Then you had the UMPC era where Windows made sure that adapters made for PCs would also work on UMPCs.

Fast forward to today, and I just have to ask: What the heck happened to video input on portable devices!? Most devices have HDMI output these days, with some even featuring component, composite, and VGA output (via adapters). Video input on the other hand, is nowhere to be found. It’s not part of the pinout of any mobile device’s connector, and I haven’t been able to find a single accessory that simply takes video from a source and sends it to a mobile device. There’s the Slingbox, various security cameras, baby monitors, and other video related accessories, but nothing that simply lets you input a video signal.

I think this is something that people don’t know they’re missing. RCA input would be good, HDMI input great, and both would be awesome. It would allow you to use a 10 year old portable DVD player to output video to one or more iPads in a car, eliminating the issue of getting video content onto an iPad when kids tend to have DVD collections rather than iTunes libraries (especially in countries like here in Norway where downloadable content in the right language is rare). It would allow you to hook up old game consoles, and even make them portable (1080p Xbox 360 or PS3 on an iPad 3, anyone?). A tablet could even replace a TV in a small mobile home, just have the receiver there and hook up the tablet. You could have a tablet in the car, and have the option to either run it on its own, or simply mirror the image from a smartphone which already has GPS and a 3G connection. My horribly video playback-incompetent iPad could serve as a monitor for my “I’ll play anything”-Galaxy S II on trips, combining one device’s storage and playback capabilities with another device’s screen. Heck, if my S II could push 1080p video to an iPad, I would seriously consider buying the iPad 3.

The possibilities are endless, but for this to make sense, the hardware needed would have to be reasonably priced. It’s possible to buy monitors with all the inputs you need separately after all, so there would have to be an advantage to not simply doing that. Still, examples like pushing 1080p video that the iPad 3 itself can’t play to its screen isn’t really something you can do with stand-alone monitors, simply because you wouldn’t be carrying around a separate 10-inch, 1080p+ resolution, battery powered monitor, even if you could find one and afford it.

I know it’s possible to make a third party accessory that would do this right now, by simply using the same methods that existing baby monitor/security cameras use. I don’t know what Apple’s policy on something like this would be, but technically it should also be possible to make one that plugs into the iPad’s dock connector. The same might be possible with USB host capable Android devices, but this is all just speculation. Considering that you could buy an adapter for a Game Boy to do this ten years ago though, and the wide array of such adapters for PCs, I think it’s a reasonable assumption.

I just don’t understand at what point manufacturers suddenly decided this wasn’t a useful feature anymore.