Resolution: 240 × 240, 220 DPI Viewing Angle: 180° Communication Method: NFC (Near Field Communication) Battery: Battery-free Materials: Aluminum alloy frame + front and rear glass panels Weight: 12.7g ±0.5g Displayable Content: Text, barcodes, QR codes, and images Appearance: Gray frame + matte white panel Companion App: EINKY Compatible Mobile Systems: Android / iOS