An electrotactile apparatus has an electrode-array unit and a driver unit for generating a haptic feedback to a user. The electrode-array unit uses electrodes to electro-stimulate the user's skin with pulsed voltage signals generated by the driver unit, inducing excitation currents flowing in the user to generate the haptic feedback. The driver unit is self-powered or wirelessly powered for supporting untethered electrotactile stimulation to the user. A common counter electrode installed on the driver unit contacts the user's skin and collects the excitation currents returned from the user. Advantageously, the common counter electrode is located on an outer surface of the driver unit and the driver unit is substantially flexible, facilitating the common counter electrode to seamlessly contact the user's skin for achieving a stable electrode-skin interface while positioning the driver unit as a whole on the user's skin to provide untethered virtual touching experience to the user.