The HaPlay GO Zero Upcycles an Old Smartphone with postmarketOS and a Slick Pocket Cyberdeck Case

Pseudonymous maker "mongkeelutfi" has become the latest to build a pocket-friendly cyberdeck for on-the-go use — but rather than the usual Raspberry Pi, this one is made using an upcycled smartphone running postmarketOS.

"Hi gais, this my pocket Linux [machine]," mongkeelutfi explains of the slick-looking portable. "I buil[t it] from [a] very old Xiaomi Redmi 2 smartphone and replace[d] the OS [Operating System] with postmarket[OS]. Add [a] keyboard and USB port for expansion and pack it with [a] 3D printed case. This is very cheap. Just $42.91."

The gadget's 3D-printed housing uses a relatively square layout, placing the touchscreen display above an off-the-shelf battery-powered Bluetooth keyboard. A USB Type-C connector at the top allows for battery charging, while an internal hub provides two USB Type-A ports for external accessories.

In similar designs, you'd crack the case open to find a Raspberry Pi or other single-board computer and a separate battery control board. In mongkeelutfi's build, dubbed the HaPlay GO Zero, there's no Raspberry Pi to be found; instead, the case houses an old Xiaomi Redmi 2 Android smartphone flashed with the postmarketOS Linux distribution — meaning the battery to keep it ticking over is already handled by the phone itself.

Unlike stock Android, postmarketOS is designed to provide a full Linux desktop environment — KDE Plasma on the KWin Wayland window manager — making the gadget entirely usable as an on-the-go Linux terminal for remote access and local use. There's only one flaw, which could be fixed with a quick design tweak: "I made the [headphone socket] hole in the wrong position," mongkeelutfi explains, "so the jack can't go in."

More information is available on mongkeelutfi's Reddit post; at the time of writing, 3D print files had not been shared publicly.