Vietnamese website Tinh t? has once again gotten its hands on what appears to be prototype Apple hardware. This time the site has videos of what it says is a white iPhone 4, running some type of test build of iOS. However, while the version number says iOS 4.0, it shows radically different user interfaces for using Springboard folders as well as iOS's task switcher.

Like other prototype iPhone 4 devices uncovered last year, the capacity of the device is listed as "XXGB," but the system reports that it has 64GB of flash storage. The iPhone 4 currently maxes out at 32GB, so if this prototype is the genuine article—and it appears it is—the white iPhone 4 may come in a 64GB option. Apple might use it as an exclusive to make the white iPhone 4 more desirable, or (injecting a little wishful thinking) it may offer 64GB iPhone 4s across the board as a stop-gap measure to keep sales up until an expected fall launch for the iPhone 5.

The version of iOS running on the device is listed as iOS 4.0, build 8A216, which we believe may be a build prior to iOS 4's public release, but it shows radically different user interfaces for iOS's multitasking and app folders. As seen in the video below, double-tapping the prototype's home button brings up an Exposé-like view showing a 3x3 grid of app screen thumbnails. Tapping a screen moves to that app. Tapping and holding will invoke the now familiar jiggling icons with a top-left "X" to quit an app. At the top is a translucent button to start a Spotlight search.

Oddly, the Exposé-style task switching seems more "Apple-like" than the current implementation with a linear scrolling row of icons. At first blush, it seems more user friendly than what we have come to expect in iOS 4, and Engadget seems to believe that it could be a preview of what's in store for iOS 5. It's worth noting, however, that the UI makes no accommodation for accessing iTunes, music player controls, or screen orientation lock. Nor does it appear to be able to access recently used apps that are "frozen" and not currently running. If Apple could meld those functions with an Exposé grid view, we would consider that an overall improvement.

The other major UI difference is in the app folders feature. Instead of appearing as a split homescreen, the folder opens as a translucent rounded rectangle overlay, similar to HUD controls used widely in Leopard and Snow Leopard. However, the style currently used in iOS 4 is more like the iPad-style popover windows that seem to be migrating to Lion.

There are slight differences in the hardware from shipping iPhone 4 models, such as the camera and home button styling, so it's difficult to tell how early this purported prototype might be. As 9to5 Mac noted, the presence of Touch Fighter—an internal demo app developed by Apple—as well as debugging controls, suggest the prototype is legitimate. Tinh t? has in the past had access to prototype iPod touch and iPhone 4 hardware.

How closely the final white iPhone 4 resembles this supposed prototype won't be known until Apple finally ships the device. The UI differences may also merely be prototype implementations that were ultimately abandoned by Apple in the process of developing iOS 4.