We guessed that the iPhone 3Gs was capable of a 1080p HD video playback, but now here we have the proof!

Apple claim the iPhone 3Gs’s maximum video playback is 640×480, but iLounge linked to a Chinese forum post claims different stating that the 3GS could in fact do 30Mbps 1080p playback.

All we needed to do to test it out was to download the free FileAid app. A whole bunch of HD trailers from Apple’s QuickTime trailer site were tested out. Some videos were shot with a Lumix DMC GHI and some other random videos generally successful, however there were some major blips during playback. The Avatar trailer constantly crashed the phones audio driver. On the iPhone 3G we constantly got an error message on pretty much any resolution. As evidenced by the bugs this is clearly not ready for prime time yet, we are however, hoping that Apple are busy polishing this up and preparing to unlock this functionality. To see the video go to engadgetmobile.com