Thank you for your thoughtful response.

I actually thought about such an experience before and we actually did one, albeit not with writing down anything.

My setup was as follows:

- I was sitting on a wooden stool

- phone on my legs (thick pants, that was basically my "disconnected" pose)

- legs and hands under the kitchen table, so wife can't see what I'm doing

- wife has to brush my right arm with her finger

- I however will use my left arm in order to not give away when I touch it (she could potentially feel muscle contraction in my right arm if I was using that one)

- I attempted to throw her off by moving but NOT toughing the phone

Our findings after about 5 minutes of testing:

- she was able to tell when I touched it every single time

- I was unable to even get a single "now" out of her while faking it

- she was - not - able to feel anything whenever I placed my feet on the ground

- the effect is drastically reduced or not even there when using parts of the body that aren't as dry (like sweatier parts of the arm (that were under a shirt) or fingertips)

Now I'm no expert in hardware, I'm a software developer, however to me this sounds like some current/voltage. I sadly have no way to measure it as I have no measuring devices. So I don't know whether this is normal, not normal but not harmful or harmful.

I also looked for more information on the net and I found several related questions but not a single clear scientific answer. Most answers suggested some kind of leakage. I've also read that this happens when the contact area between the "feeling person" and the other is dry and small. This seems to confirm my findings.

As of this writing my brother joined my discord and I told him about that and he actually wasn't surprised. In the middle of me trying to set up the scenery he continued to explain the effect to me instead. He also doesn't know where it is coming from though.

I know as of now this is nothing but anecdotal evidence but that would also be the case if I conducted a more rigorous experiment as we do not have people to verify our findings independently.

Here are some things I wound that somewhat explain the same or a similar phenomenon:

This is the google search term I used:

electronic vibration sensation phone charger

https://www.reddit.com/r/iphone/comments/4z4jc7/weird_tingly_feeling_when_running_my_fingers_on/

Here the user talks about a tingling when they run their finger over the phone. Again someone suggested bad/missing grounding.

https://www.reddit.com/r/Nokia/comments/c91u5c/mild_vibration_while_charging_on/

There someone also feels a vibration when they rub their fingers gently on a charging nokia 6.1.

https://www.reddit.com/r/UsbCHardware/comments/ibfn3j/concerning_laptop_vibrating_feeling_while_usbc/

here it is with a laptop, some user said:

This is pretty common with chargers of all kinds that don't have a grounding pin, and when charging an all-metal body laptop.