アプリは、訪問者がそれを押したときに玄関の呼び鈴が取る写真を表示することができます。
The app can show the photo the smart doorbell takes when a visitor presses the doorbell button wherever you are.With the photo, you can tell who is the visitor,and decide whether to take action ,like open the door or just call the person.It is very convenient and safe.