When someone rings the doorbell, your phone receives an immediate notification.You can open the door remotely through ToSee app and communicate directly through your mobile phone. Real-time and two-way intercom system with an echo canceller There is a passive infrared sensor built into the video doorbell, which could capture the slightest movement. Real-time monitoring is available. One can watch the video anytime and anywhere through your mobile phone and never mind the danger of opening the wrong door or the embarrassment of having visitors wait while no one at home. HD video and two- way audio make your communication much clearer.