Kyocera Echo for Sprint, The closest thing Android has had to a dual-screen phone was the Samsung Continuum, which didn’t really make much of a splash. Kyocera has done much better with the Echo.
Hardware
It feels solid and well-built. When folded it’s almost the same length/width as the original Motorola Droid, but it’s a bit thicker.It’s also heavier than the already heavy-ish Droid.
When folded out, the Echo is very flat and thin, and the two screens form one 4.7-inch (diagonal) screen that’s somewhat square and awkward to hold. Kyocera did a good job of minimizing the gap between the two screens. It’s big enough to lose a line or two of text, though, so some scrolling may be required when reading pages spread out over two screens.
The 5-megapixel camera seems fairly responsive, It can shoot video at 720p, but the relatively low resolution of the phone’s screen won’t show that off. You’ll only see it once you’ve moved it to your computer, or another device.
Software
The Echo ships with Froyo (Android 2.2), but they have made some pretty nice tweaks in the phone’s software, mostly by way of customizing some standard apps. E-mail, for example, can be set up more like Outlook on your computer, with one screen showing the message list, and the other displaying the highlighted message.
The same concept is applied to the Gallery, where one screen is for viewing the pictures while the other displays thumbnails. Also, when typing (in the messaging app, for instance), the entire lower screen becomes the keyboard, which means GIANT keys.
Performance
Unfortunately, it wasn’t much of a speed demon. There was noticeable lag when switching between homescreens, between apps, and when opening new apps. It wasn’t slow, but it wasn’t very fast, either. Simultaneously running two apps on screen (with others in the background) just seems to overtax the 1GHz Hummingbird processor. The 1GB of RAM probably helps, but not enough.
Another major blow is that, we are now living in a brand new 4G world and this is a 3G phone.
They take a very innovative approach to battery life. It ships with a second battery and a travel charger that will charge the phone and the extra battery at the same time.