You're looking at the dual-screened YotaPhone. You can buy it, if you live in Russia, Germany, France, Austria or Spain.

Priced at €499, it runs Android and combines a standard 4.3-inch 720p LCD touchcreen up front with a 4.3-inch E-Ink screen around the back. The phone runs on a 1.7GHz dual-core processor, backed by 2GB of RAM.

The low-powered E-Ink screen can be left on at all times and will only update new notifications that come in. It's also presumably great for reading. Combining the fact that it doesn't take up much juice, you'll be able to use the phone longer without charging it so often.  Will the YotaPhone be available elsewhere, we wonder? [TechRadar]