Intercom app

If someone presses the button, two things happen at the same time. Your phone receives a push notification via Android or iOS, and the doorbell makes a live connection for video and audio. Those two are separate. If the notification does come in but the screen remains black, the connection with the doorbell is failing. If nothing at all comes through, it's usually because of your phone's notification permissions or battery saving: many devices put apps you rarely open on a low power setting after a few days, so a notification sometimes only appears when you touch the screen again. Most doorbells use half-duplex audio: you talk alternately, like on a landline phone. You only hear the visitor again when you release the speaker button. That feels uncomfortable, but it prevents the speaker from picking up its own sound again. More advanced intercoms work full duplex, allowing you to talk to each other. Keep in mind that the visitor hears your voice from a small speaker in the doorbell; on a busy street, that can sometimes be too soft. Looking back only works if something is actually saved. This can be locally on a memory card in the doorbell, on a base station or recorder inside, or outside the door in the cloud. Local storage is completely in your own control, but those images disappear if the device itself is taken with you. If you want to be sure that the images will remain, then storing them outside the door is the safer choice.

Almost every app has one account as the owner. That account is the first to ring the doorbell and then invites roommates or colleagues to their own email address. Never give your own login credentials. If you do, you will have to change the password of the main account and re-link all devices when moving or when a departing colleague leaves. With separate accounts, you can take someone out of it with a few taps. Shared users usually have less rights than the owner: they can watch and record live, but not change the settings or delete saved images. Check for each user whether the doorbell is turned on. In a company building, you often want everyone to be able to watch, but only a few people to actually be able to open it. A common mistake is that everyone turns on all notifications. If five phones are ringing at the same time, eventually no one responds. Turn on notifications for those who can open them at that moment and let the rest open the app manually. Some apps have time schedules, so the call goes through on other devices outside office hours instead of inside.

An intercom app is connected or disconnected with the connection. Wi-Fi at the front door is often weaker than you think: the router is usually located in the middle of the house, and an exterior wall, a meter box, or floor heating significantly dampen the signal. A doorbell that turns on one line gives flickering images and delayed notifications. A network cable to the doorbell or to the indoor unit provides a stable connection that is not dependent on Wi-Fi, and also delivers power immediately via PoE. For power there are three routes: a battery that is periodically charged, the existing doorbell transformer, or PoE via the network cable. A battery is usually the fastest to install, but in winter and with many passersby it noticeably runs out faster. If there is already doorbell wiring, then the transformer is usually the easiest. Please check whether it provides enough power, as older doorbell transformers are often too light for a doorbell with a camera. Remote opening requires a switching contact that operates the door lock or door opener. In most systems, that contact is located in the internal unit or in a separate relay, not in the doorbell itself, so nothing hangs outside that someone can use to open the door. The lock also requires its own power supply. If there is already an old intercom installation with a door opener, please check beforehand which wires are connected. In older buildings, that wiring is rarely documented.