I don't think that you teach the way to operate a personal computer by phone.
It will be fighting with a high probability, or it becomes a bad mood even though it does not become fighting.
The one who teaches how to operate the keyboard and mouse based on images of a computer screen in the head, however,
the other who is taught is looking at the actual PC screen, but the screen is different from "the image in the head of the teaching person".
After all, "No icon like that", "I can not enter", "No way" "Did you pressed the OK button?" will be flying across,
And, in most cases, Each of them says "Don't you understand such a thing" or "Can't you properly give instructions" with treating each other incompetent. While doing unpleasant feelings, this attempt will be a failure with a high probability.
However, when both share the same screen in remote environments, this is unlikely to occur.
It is because the target is fixed concretely.
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I previously used software called VNC (Virtual Network Computing) to maintain personal computers in Kagoshima, my wife's parents' home.
This is what allows me to display the PC screen of Kagoshima on my home browser, and directly manipulate that screen.
In short, it is "hijacking of PC".
Using this software, I was able to reliably maintain the PC of Kagoshima.
However, my wife said to me,
"It was very bad feeling that the PC's mouse moved without permission, and the window was opened and characters were entered"
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However, even if it was "hijacking PC", I can not do anything unless I activate the program that I had previously loaded.
However, in the case, when I went to my hometown of Kagoshima's wife before, I loaded an automatic launch program ("Trojan horse" so called), so I can hack the PC without problems.
In other words, any system security can be broken by 100% if you make a intruder.
Even if you do not make an intruder, if you put "horses" inside the system, it is a piece of cake to to extract any information from the outside.
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So, when you see that my family can easily make others operate their smartphone,
"They are really courageous."
I think that.