I have the free plane in Firebase - I have 100 simultaneous realtime connections. But I didnt understand one thing: Now, No one connected to my app, and in Firebase - It is
A simultaneous connection is equivalent to one mobile device, browser tab, or server app connected to the database. This isn't the same as the total number of users of your app, because your users don't all connect at once. For example, apps with 10 million monthly active users usually have fewer than 200,000 simultaneous connections. Your max simultaneous connections depends on your total user count and the average time users spend in your app.
Source : Firebase Documentation on Realtime Database Limits
Q : I have 100 connections in general or maximum 100 simultaneous realtime connections?
A : It's 100 simultaneous realtime connections.