You want the Nokia 8110 "banana phone" [0], a re-release of the phone Neo uses in The Matrix. Unfortunately there's no US version :(
[0] https://www.amazon.com/Nokia-8110-TA-1067-2-45-inches-Unlock...
It's the best, beats the rest, cellular, modular, interactivodular.
Re:A new jailbreak for a new era
by yjftsjthsd-h on Monday November 23, 2020 @08:26PM
(#25194178)
So are you intentionally hinting at the Light Phone, or is it news to you that someone has implemented exactly what you're describing? :) (https://www.thelightphone.com/)
First time seeing that, but it comes preatty close!
Still, being able to write your own apps for it would be nice. Even if very low level APIs & you would have to handle distribution yourself if you wanted to share them would be fine. But I don't see any information about that after quickly checking their page.
BTW, a simple mobile terminal with cellular connection that you can program could be preatty useful in comparison to hacking a regular Android phone to only do what you need could be useful as well. For stuff like single use online terminals to give to field crews.
Application could be very basic (calendar, address book, calculator, alarm, etc.) - by default. Or users could make their own simple apps - nothing fancy, Arduino like cooperative multitasking, simple screen drawing, maybe a few widget helpers.
I can imagine this being a fun thing to use & play with. :)