Q:

Can you die when your plugged-in mobile phone falls in the bathtub?

I have questions related to the safety of using mobile devices in the bathtub. I always thought the danger in dropping it or getting water on it is mostly to the device, not to the person, but a recent accident made me doubt that.

Is it possible to die from the charging end of a high-power USB charger (which can deliver up to 20V) in the bathtub?  (The charger itself would not be in the water, nor would be the wall cable.) 
Is a mobile device dropped in the bathtub dangerous (to the person, not the device ;-) )?
Are there known instances when a submerged mobile device started to burn? (After all, the battery contains Lithium which can burn under water, and Lithium battery fires cannot be extinguished with water.)

A:

The phone itself can’t develop enough potential to cause a shock with burns - the battery is only 3.8V. Further, any stray currents would have been local to the phone, and would not have found a body path.
What might have happened is that she reached for the cord to plug in the phone, and she got shocked by the cord, and dropped the phone... and was not able to get the cord away. Very sad - what an unfortunate way to lose someone.
Then the underlying problem leading to this would be two things: a faulty charger, and a non-functioning or not-present GFCI that should have tripped.

