Russian company "Yota Devices" introduced a new mobile device in a revolutionary design and TWO displays:
Color display at the front and Black-White E-Ink display at the back side.

Technical specificationsOS: Android™ 4.4, KitKat®
CPU: Qualcomm® Snapdragon™ 800 2.2 GHz quad-core
FORM FACTOR: Monoblock with full touch capacitive screens on the front and back
DIMENSIONS: 144.9 x 69.4 x 8.95 mm
AUDIO3.5mm AV connector, FM radio
Audio formats/codecs: AAC LC, HE-AACv1 (AAC+), HE-AACv2 (enhanced AAC+), AAC ELD, AMR-NB, AMR-WB, FLAC, MP3, MIDI, Vorbis, PCM/WAVE.
Supported files types/container formats: 3GPP (.3gp), MPEG-4 (.mp4, .m4a), ADTS raw AAC (.aac), MPEG-TS (.ts), 3GPP (.3gp), FLAC (.flac), MP3 (.mp3), MIDI Type 0 and 1 (.mid, .xmf, .mxmf), RTTTL/RTX (.rtttl, .rtx), OTA (.ota), iMelody (.imy), Ogg (.ogg), Matroska (.mkv), WAVE (.wav)
VIDEOFull HD 1080p
30fps
Video formats/codecs: H.263, H.264 AVC
MPEG-4 SP, VP8.
Supported file types/container formats: 3GPP (.3gp), MPEG-4 (.mp4), MPEG-TS (.ts), WebM (.webm), Matroska (.mka).
NETWORKGSM/EGPRS 850, 900, 1800, 1900 MHz
WCDMA, DC HSDPA (rel. 8, cat. 24)
HSUPA (rel. 7, cat 7) bands 1 (diversity), 2, 5 and 8
LTE (rel. 9, cat 4) bands 3, 7 and 20, VoLTE
MEMORY2GB RAM, 32GB eMMC
SENSORSAccelerometer, compass, gyroscope, proximity sensor, amibient light sensor
CAMERAMain: 8MP AF, LED Flash
Front: 2.1MP
COLOUR SCREEN5” AMOLED
Full HD 1920x1080
16M colors
full capacitive touch
442ppi
Corning Gorilla glass 3
ALWAYS-ON SCREEN4.7”
Electronic Paper Display
960x540
16-level gray scale
full capacitive touch
235ppi
Corning Gorilla glass 3
CONNECTIVITYWiFi 802.11 a/b/g/n/ac (VHT20, MSC 8)
MicroUSB 2.0 (SlimPort®)
Bluetooth® 4.0
NFC
A-GPS + GLONASS
Nano-SIM
POWER MANAGEMENT2500mAh
Wireless charging
WEIGHT145 g
Source: http://yotaphone.com/gb-en/