Microsoft’s Duo is a unique folding device that makes calls and text messages. However, Microsoft is adamant that the Duo is not a phone. Microsoft staff are now using the device in the wild. Two 5.6 inch displays that can fold into one 5.6 inch display. Each screen has a resolution of 1800 by 1350. Qualcomm Snapdragon 855. Fingerprint sensor. No 5G. Android OS.