[fit2rule]

The OpenPandora / Pyra Handheld consoles represent what you describe .. and there is a budding ecosystem around the scene.

I think the problem with these projects is that there isn't really a rigorous, solid systems-software approach to building the base platform for other developers. There used to be an art to designing operating systems and environments/frameworks for others - but this subject has been well and truly usurped by the marketing executives who want to exploit the devs rather than make them successful.

[duskwuff]

Ehhh. The OpenPandora has been out of production since 2013, and the Pyra has been in development hell since 2014. The ecosystem surrounding these devices is not in a healthy state, in large part because there aren't a lot of them left.