3D spectacles; accelerometers; acoustic sound alarms; acoustic conduits; acoustic couplers; audio- and video-receivers; azimuth measuring instruments; binoculars; camcorders; photographic cameras; integrated circuits chips; cinematographic cameras; directional compasses; computer memory devices; recorded computer programs for operating and controlling 3D spectacles, smartglasses, virtual reality glasses, smart devices, drones, and robots for personal, hobby, or household maintenance use; recorded computer operating programs; recorded computer peripheral devices; recorded computer software for operating and controlling 3D spectacles, smartglasses, virtual reality glasses, smart devices, drones, and robots for personal, hobby, or household maintenance use; downloadable computer programs for operating and controlling 3D spectacles, smartglasses, virtual reality glasses, smart devices, drones, and robots for personal, hobby, or household maintenance use; downloadable software for operating and controlling 3D spectacles, smartglasses, virtual reality glasses, smart devices, drones, and robots for personal, hobby, or household maintenance use; downloadable computer software applications, namely, software for operating and controlling 3D spectacles, smartglasses, virtual reality glasses, smart devices, drones, and robots for personal, hobby, or household maintenance use; computer hardware; computers; correcting optical lenses; data processing apparatus; dictating machines; distance recording apparatus in the nature of electronic distance meters; editing appliances and apparatus in the nature of editing machines for cinematographic films; electronic pocket translators; Global Positioning System apparatus; goggles for sports; hands-free kits for telephones; headphones; integrated circuits; interfaces for computers; laptop computers; surveying instruments, namely, levelling staffs and rods; levelling instruments, namely, level indicators; levels, namely, surveyors' levels; magnifying glasses; microphones; microprocessors; mileage and kilometer electronic data recorders for vehicles; mobile telephones; cell phones; cellular phones; monitoring apparatus in the nature of electronic data recorders that record distance travelled and closed circuit television cameras; navigation apparatus for vehicles; on-board computers; electric navigational instruments; optical character readers; printed circuits; printed circuit boards; optical prisms; central processing units; range finders; telemeters; scanners; semi-conductors; smartglasses; smartphones; sound recording apparatus; spectacles; eyeglasses; speed measuring apparatus in the nature of speed indicators; speed checking apparatus for vehicles in the nature of electronic speed detectors; personal stereos; stereoscopes; stereoscopic apparatus in the nature of stereoscopes; sunglasses; surveying instruments; surveying apparatus and instruments; telephone receivers; telephone apparatus; telephone transmitters; telescopes; time recording apparatus; time clocks; transmitters of electronic signals; telecommunication transmitters; video recorders; video telephones; wearable activity trackers