The Kyocera Echo had so much potential, but we were left under-impressed with the hardware design. Even if it won’t end up replacing any of our favorite single-screen smartphones, it still planted a seed: is there a way to make a dual-screen Android that’s useful, affordable, and well-made? While it’s still a ways off from being a commercial product, a prototype design from Imerj and Frog revisits the idea, and seems to have learned from at least some of Kyocera’s mistakes.

For starters, the prototype, known only as the “2-in-1 smartpad”, uses its own custom software, built as a layer on top of Gingerbread, to allow apps to share the screen space or spread out tablet-style; developers will need to modify apps to support the dual-screen spread mode, however. There’s no fragile-feeling elaborate hinge mechanism here; the two halves of the prototype are attached by a simple single hinge in the middle, and the phone is held shut with magnets when fully-closed. The only downside we can see there is that both screens are exposed all the time, which is just asking for extra smudges and damage. Both screens are 4-inch WVGA AMOLEDs.

While the hardware is still up for changes, being an in-development prototype, the phone should have a TI processor, 1GB of RAM, and lack external storage options (though there’s the possibility for models with up to 128GB of internal flash). When opened, the smartphone is just 7mm thick, so even folded-shut it’s not overly bulky.

No word yet on when to expect the device, nor on cost, but especially with all that storage, this could end up being a real wallet-drainer. If it saves you from buying an expensive tablet, though, it might just be worth it.