ESP32 Camera suports up to 4 video cameras. The camera module and the phone must be on the same network.
If the camera module uses face racogniton sketch, the url address for streaming in the application must be: http://cameraIP:81/stream (for example: http://192.168.1.123:81/stream). To change resolution of the camera module, enter the camera IP adress in the web browser, not in the application (for example: http://192.168.1.123).
For programming the ESP32Cam module, also this arduino sketch can be used: https://github.com/arkhipenko/esp32-cam-mjpeg-multiclient It supports up to 10 clients. The resolution of the camera can be changed only in the sketch. The url address in application must be http://cameraIP/mjpeg/1 (for example: http://192.168.1.123/mjpeg/1)
Sometimes takes time for connection the camera, please wait.
In the application settings, all cameras labels can be changed.
For reaching the camera from everywhere using different network, the camera port must be open in the router (port forwarding). The default camera port is 80, it can be changed in the sketch for security reasons. For face recognition sketch default port is 81. It is not necessary to be changed.The url address in the application then must be: http://StaticIP:Port/mjpeg/1 or http://StaticIp:81/stream if the face recognition sketch is used.