A custom application for an online intercom installed in a residential or office building. Allows you to accept a call, see the guest, talk to him and open the door. You can use the application at any time, open the door for yourself, or just see what the weather is like outside and find out the real air temperature in additional information. The application supports three levels of the hierarchy of user rights, Owner, Administrator and Subscriber. Users of the Owner and Administrator level can manage the accounts of the Subscribers and their electronic access keys.