Does the camera have to use 4g traffic or WiFi? Is there a camera that can be directly monitored by mobile phone without traffic or WiFi?

Well, ..........., it's all the result of cheap cameras. .....

.. In fact, ................ car cameras don't need wifi. .....

..... A high-quality camera can save the video on the local memory card, or compress it and then transmit it through wifi (which can greatly reduce the traffic). ............, besides, what you said:

No traffic, no WiFi, direct monitoring with mobile phone.

What do you mean, ................. doesn't know ... hard to understand?