GammaOS Nano v1.4.1 (GKD 350H Ultra) Release Notes

Patreon Exclusive Release
Password obtained from Patreon for GammaOS Insider tier supporters: https://www.patreon.com/GammaOS/posts/166615763
This release will become publicly available to non-supporters at a later date. The password will be posted on Patreon.

Release Date: 13th August 2026.

This is a whole new GammaOS

v1.4 is not an incremental update. On the GKD 350H Ultra, GammaOS Nano is the primary UI, and it is not a launcher, it is a whole micro-OS built on top of Android. It grabs the panel the instant you power on and paints a full console-style home, but underneath it is deeply integrated with the low-level Android system and the device hardware: DRM-direct rendering straight to the panel, an early-boot audio engine that sounds before the rest of the system is even up, and native power and sleep management. There is no heavy Android launcher loading in the background, no bloat, and no waiting. It boots straight to a console-style experience that is fast, lean and built for a controller first.

This build runs entirely from a microSD card and leaves your device's internal stock firmware untouched, so you are never locked in. It is based on GammaOS Core (Android 14 / LineageOS 21), and you can switch freely between GammaOS Nano and the full GammaOS Core Android experience underneath whenever you like. To go back to stock, just remove the card.

Device Notes

• Switching between normal USB and OTG mode: use the built-in USB app to switch between normal USB (gadget) mode and OTG (host) mode on the device.

Known Issues

• DraStic RetroAchievements currently supports Softcore mode only. Hardcore mode is pending approval from the RetroAchievements team, which can take up to around 6 months if they agree to it.

What's New

For the full list of changes in v1.4.1, see the changelog:
https://github.com/TheGammaSqueeze/GammaOSNext/wiki/GammaOS-Next-Changelog#v141-august-2026

GammaOS Nano gives you three complete home themes (DSi System Menu, PS3 XMB and Minima) that you can switch between at any time, a much-improved built-in DraStic-nano DS player with RetroAchievements (Softcore) and Quick Resume, custom and looping video wallpapers, an in-game overlay on a power-button hold, reworked sleep and wake, and self-contained music, video and photo players, a controller-first web browser, IPTV and Internet Radio, system-wide Network Shares (SMB/NFS/WebDAV/FTP) and a global search.

Learn More About GammaOS Nano

A full guide to everything GammaOS Nano can do, its themes, players, settings and hidden features, is here:
https://thegammasqueeze.github.io/GammaOSNano-WIKI/

Before You Download

This is a single SD card build. It boots into GammaOS Nano as the primary UI and lets you switch to the full GammaOS Core Android experience freely.

Download the package

Download from this release page:

• GKD_350H_Ultra_GammaOS_Nano_v1.4.1.7z.001 (the firmware image, password-protected)
• SDDiskTool_v1.69_SDBootOnly.zip (the SD card creation tool, Windows)

Extract

Extract GKD_350H_Ultra_GammaOS_Nano_v1.4.1.7z.001 with the password from Patreon (7-Zip). You will get a single image file:

• GKD_350H_Ultra_GammaOS_Nano_v1.4.1.img

Also extract SDDiskTool_v1.69_SDBootOnly.zip.

Install

This is an SD card install using the SDDiskTool (Windows). Do NOT use DD, Win32DiskImager or balenaEtcher - only the supplied SDDiskTool will work. Full step-by-step installation instructions are here:
https://github.com/TheGammaSqueeze/GammaOSNext/wiki/GammaOS-Next-Installation#gkd-350h-ultra

Note: GammaOS Nano runs entirely from the microSD card. Your device's internal storage and stock firmware are left untouched. To return to stock, power off and remove the card.

Overview

GammaOS Nano v1.4.1 is a ground-up rebuild of the GKD 350H Ultra experience, based on GammaOS Core (Android 14 / LineageOS 21). Rather than loading a heavy Android launcher, it boots straight into a native, console-style home built for handhelds, with the full GammaOS Core Android experience one switch away. This release focuses on a fast boot-to-play experience, three full home themes, a much-improved DraStic DS player with RetroAchievements, custom and video wallpapers, and a lean footprint, all running from an SD card that leaves your stock firmware intact.

Full Changelog

The complete, detailed changelog for v1.4.1 is available here:
https://github.com/TheGammaSqueeze/GammaOSNext/wiki/GammaOS-Next-Changelog#v141-august-2026

Support

For assistance or feedback, please open an Issue here:
https://github.com/TheGammaSqueeze/GammaOSNext/issues

Thank you for supporting GammaOS development and helping improve GammaOS Nano for the GKD 350H Ultra.