While the Crowdfunder for the Librem 5 successfully finished, I want to shed some light on possible alternatives to it for people that want to run GNU/Linux on Smartphone hardware. First up: postmarketOS
postmarketOS (short pmOS) is a relatively new project. A little more than two months ago the projects founder ollieparanoid published a [blog post](https://postmarketos.org/blog/2017/09/03/100-days-of- postmarketos/) titled: 100 days of postmarketOS, listing pretty amazing accomplishments in these first 100 days.
Differing from other attemps at getting a non-Android-Linux1 onto smartphones, pmOS aims to target multiple devices with small device specific parts and a set of software that then is interchangeable between multiple devices. It is based on Alpine Linux, a distrOnly recentlyibution designed for "power users who appreciate security, simplicity and resource efficiency". Currently, 17 devices are supported (not counting QEMU targets) and in various states of support. The best supported devices currently is the good old Nokia N900, as it pmOS can stand on the shoulders of giants here with regard to mainline Linux support.
There is not one interface, due to a modular approach of pmOS and in order to support devices that are less capable. Currently, supported interfaces (more a "will be" than an "are" statement as far as I could gather) include good old Hildon (known from Maemo) and Plasma Mobile.
So, to boil it down: Device agnostic, UI agnostic, open and friendly.
postmarketOS is technically not a GNU/Linux OS, as it is built around