A device is provided for applying an on-skin sensor assembly to skin of a host. The device comprises: a base configured to secure a housing, wherein the housing is configured to receive an electronics unit, wherein the electronics unit is configured to generate analyte information based on a signal from a sensor; a sensor insertion mechanism configured to insert the sensor into the host, and including a needle carrying the sensor, a rotatable wheel, and a linearly translatable needle carrier; and a trigger configured, in response to being activated, to cause the rotatable wheel to rotate, which in turn causes the linearly translatable needle carrier to translate toward the host to implant the sensor, and subsequently to translate away from the host to withdraw the needle from the host.