I found this. Its a Raspberry Pi in a brick case with a screen and a 4G modem.

I REALLY wanted to do a pi phone, and while it's very possible to make a working phone/tablet out of one, their power consumption is absolutely awful. Most of the linux capable SBC's can't do low power.

I want an 8" linux touch screen with 18h of moderate usage batter life, I'm even willing to carry around a separate 4g access point.

Furi's FLX1s seems like a valid alternative.

CM5s have 16GB of ram, some people might be building a postmarket os port for it too. Just need someone to design phone hardware for it.