Sxmo: a text-centric mobile user interface
Sxmo, short for "Simple X Mobile", is described on its web site as ""a minimalist environment for Linux mobile devices""; it offers a menu-driven interface that is controlled with the phone's hardware buttons. Sxmo enables the user to send SMS messages from a text editor and is entirely customizable with shell scripts. This peculiar mobile user interface significantly differs from the prevailing approach—but it works.
While mobile user interfaces such as Phosh, KDE Plasma Mobile, and Lomiri have some differences between them, they are all rooted in the same philosophy. They center on touch-based interactions and display apps through icons, an approach influenced by the conventional point-and-click paradigm of desktop user interfaces. However, on the desktop, a text-centric approach centering on keyboard input and terminal programs following the Unix philosophy has remained popular among advanced users. Sxmo aims to offer such an environment for mobile devices.
There are two flavors of Sxmo: Xorg or Wayland. The Xorg version is based on a couple of forks of tools from the suckless project, which has ""a focus on simplicity, clarity, and frugality"". This includes the dynamic window manager dwm, the menu system dmenu, and the simple terminal emulator st. The Wayland version uses some tools inspired by their Xorg counterparts, including the tiling Wayland compositor Sway, the menu system bemenu, and the terminal emulator foot. In practice, both versions work similarly, with some minor low-level differences in configuration.
Sxmo is best supported on the postmarketOS Linux distribution for mobile devices (previously covered here). Pre-built images of postmarketOS with Sxmo for various devices can be found on the download page of the distribution. Alternatively, a custom image can be built by running pmbootstrap init and choosing sxmo-de-sway (for the Wayland version) or sxmo-de-dwm (for the Xorg version) as the interface. I tested Sxmo's Wayland version by installing a custom-built postmarketOS image.