The various embodiments described herein include methods, devices, and systems for implementing radar-based touch interfaces. In one aspect, a computing device includes: (1) a casing; (2) a radar transceiver configured to detect one or more objects in the vicinity of the computing device; and (3) one or more controllers coupled to the radar transceiver, the one or more controllers configured to, for each detected object in the one or more detected objects: (a) determine whether the detected object is in contact with the casing based on data received from the radar transceiver; (b) in accordance with a determination that the detected object is in contact with the casing, identifying an input command based on at least one of: a location of the detected object, and a movement of the detected object; and (c) adjust operation of the computing device based on the input command.