They should do it. Old phones can be repurposed for stuff like smart mirrors, not having to worry about the battery in that case would be great.
Nowadays, pretty much every phone supports battery idle mode anyways, which is the same thing: They don't trickle charge the battery, they just run off the charger entirely.
If we get replace batteries, implementing this too is a negligible amount of effort.
I don't think that many phones support the idle mode I think Sony has one, Samsung only has a battery bypass when you're gaming. I think it's still a pretty rare feature but if you know something I don't please share
Yeah they're ready-to-go touchscreen interfaces/displays that can be implemented in tons of ways. I've been thinking about setting up my old Note 4 as a touch screen interface for my 3D printer, and old tablets as wall mounted interfaces for Home Assistant, which are just two possibilities.
I was poking fun at the seeming desire for a physically tethered phone as to power a device without a battery, it would need to be plugged in.
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