[Mediterraneo10]

It can't really be called the spiritual successor of the Nokia N900 if it runs Android. What made the N900 special wasn't just the hardware, it was also that it was running a traditional Linux environment, which means you could use that physical keyboard for all the hacking you can do on your desktop computer.

[Fnoord]

Termux. Also, all of these devices (F(x)tec Pro1 X, Planet Gemini/Cosmo/Astro, ...) run a myriad of OSes, so if you don't want to run Android you got alternatives (including AOSP-based). As does Nokia N900, just not out of the box back in the days.