A fixture for functional testing of an assembled wireless device, the wireless device having a data port and a removable casing concealing a battery cavity having battery contacts, the fixture comprising: a base having an opening formed therein for receiving a retainer, the retainer being rotatably mounted in the opening for rotating from a first position to a second position, the retainer for receiving the wireless device with the removable casing removed while in the first position; a connector mounted in the retainer for engaging the data port of the wireless device when the wireless device is received by the retainer in the first position; and, a battery emulator insert rotatably mounted on the base, the battery emulator insert having power contacts for engaging the battery contacts in the battery cavity of the wireless device when the retainer is rotated to the second position.