Basically every shop has portable chargers for a few yuan/hr. Also basically every modern Chinese phone has reverse wireless charging, my phone can be turned into a wireless charger if my friend's are running low or something.

Misplacing or damaging it is an issue, but so is misplacing your wallet or your car keys. I left my phone in a taxi last year because my new pant pocket is at a weird angle and the phone slips out. So my cousin was able to find the taxi through her payment app, was on the phone to him 30 seconds later and he was back 5 minutes later with the phone.

Theft is very rare in China now, this university aged student who is a regular at my local cafe and on one occasion left his brand new Macbook on the table at the cafe unattended for an hour and a half while he ducked out to run an errand. He came back, grabbed another iced coffee, and resumed what he was doing on the laptop like it was the most normal thing in the world. I'm a millennial so I would never do this, but the zoomers here grew up in such a safe and stable environment. There's a painter who regularly leaves her whole ass canvass and paint at the cafe overnight and selling those paintings is her primary source of income!