A skin treatment device such as an electric shaver, having a housing forming an elongated handle for manually moving the device along a body surface, a working head attached to the handle for effecting a treatment to the body surface, at least one detector for detecting at least one treatment parameter of the device, and a feedback indicator for indicating feedback information based on the detected treatment parameter to a user during the personal care treatment. More particularly, such feedback indicator includes a light emitter configured to emit light signals onto a mirror in front of a user.