ArkOS vs Rocknix for R36S: Which Custom Firmware is Better?
ArkOS and Rocknix are the two most popular custom firmware options for the R36S. Both replace the unreliable stock firmware with a polished, RetroArch-powered gaming experience — but they differ in approach, interface, and feature set.
Overview: What Are These Firmwares?
The R36S ships with a stock firmware that is widely considered inadequate — slow menu navigation, poor emulator configuration, and a non-existent update path. Both ArkOS and Rocknix solve these problems by replacing the entire OS with a purpose-built Linux distribution optimized for retro gaming.
ArkOS
ArkOS is a custom Linux firmware originally developed for the RK2020 and expanded to support a wide range of RK3326-based devices including the R36S. It uses EmulationStation as its frontend and RetroArch as the primary emulation backend.
ArkOS is known for its active development community, frequent updates, and excellent compatibility with R36S hardware. The developer maintains a dedicated Discord and GitHub with responsive support.
Rocknix
Rocknix (formerly known as JELOS) is a community fork that emerged from the JELOS project. It uses EmulationStation with a customized theme and RetroArch backend, similar to ArkOS. Rocknix emphasizes a clean, consistent user experience and is designed to feel like a polished product out of the box.
Feature Comparison
| Feature | ArkOS | Rocknix |
|---|---|---|
| Frontend | EmulationStation | EmulationStation |
| Emulation backend | RetroArch + standalones | RetroArch + standalones |
| Default theme | Art Book Next | Art Book Next (customized) |
| OTA updates | Yes (via Wi-Fi USB adapter) | Yes (via Wi-Fi USB adapter) |
| RetroAchievements | Yes | Yes |
| Netplay | Yes | Yes |
| Scraper (built-in) | Yes (ScreenScraper) | Yes (ScreenScraper) |
| SSH access | Yes | Yes |
| Standalone emulators | PPSSPP, Drastic, more | PPSSPP, Drastic, more |
| Update frequency | High (frequent releases) | Medium (stable releases) |
| R36S-specific support | Excellent | Good |
| Community size | Large | Medium |
Performance
Both firmware versions are built on the same Linux kernel with similar emulation backends, so raw emulation performance is essentially identical for most users. The differences lie in how each manages system resources and which core versions are packaged.
Emulation Performance
Neither ArkOS nor Rocknix gives a measurable performance advantage for systems like GBA, SNES, or PS1. Both will run these at full speed. For borderline systems like N64 and Dreamcast, the core versions bundled in each firmware may differ slightly, giving one a small edge depending on when you install.
💡 Pro Tip
Both ArkOS and Rocknix allow you to manually update RetroArch cores independently of the firmware version. If one firmware ships with an older core for a specific system, you can download the latest core directly within RetroArch without reinstalling the firmware.
Boot and Menu Speed
ArkOS tends to boot slightly faster, typically reaching the game menu in 25–35 seconds. Rocknix boots in 30–45 seconds. Both are acceptable, and this difference becomes negligible after the first boot since most users suspend rather than fully power off.
User Interface and Experience
ArkOS UI
ArkOS uses EmulationStation with the Art Book Next theme by default, producing a visually polished game library browser. The system menu is accessible via the Start button with clearly organized options. ArkOS adds several quality-of-life features like a quick game launcher (hold a button to resume the last game) and per-game aspect ratio shortcuts.
The ArkOS settings menu is detailed and occasionally complex — there are many options, which is powerful but can overwhelm new users. The official wiki is the best resource for understanding all the options.
Rocknix UI
Rocknix also uses EmulationStation with a clean theme and emphasizes a streamlined out-of-the-box experience. The settings menu is simpler and more organized, which many first-time custom firmware users appreciate. Advanced features are still available but hidden deeper in menus.
Rocknix's approach of "working well by default with minimal configuration" makes it particularly suitable for users who want to set up once and just play games without ongoing tuning.
Update Frequency and Community Support
ArkOS Updates
ArkOS releases updates frequently, sometimes multiple times per month. Updates address bugs, add new features, and keep emulator cores current. The active development means issues are typically resolved quickly, but frequent updates also mean occasional regressions that are fixed in the next release.
The ArkOS community is active on Reddit (r/r36s, r/SBCGaming) and Discord, with experienced users available to help troubleshoot issues.
Rocknix Updates
Rocknix takes a more conservative update approach, releasing fewer but more thoroughly tested updates. This "stable release" philosophy means fewer surprise breakages but also means some bugs may persist longer before being addressed.
✅ Which Should You Choose?
Choose ArkOS if: You want the most actively developed firmware with the latest features, you're comfortable with occasional minor issues between updates, and you enjoy customizing your setup. ArkOS has the most active R36S-specific community.
Choose Rocknix if: You want a clean out-of-the-box experience with fewer decisions to make, prefer stability over bleeding-edge features, or are new to custom firmware and want something that "just works."
Installation
Both firmware options are installed the same way — by flashing an image to the SD card using balenaEtcher or a similar tool. See the firmware installation guide for step-by-step instructions applicable to both.
Key installation differences:
- ArkOS: Installs to a single SD card with two partitions (system + ROMS)
- Rocknix: Same single-card layout; the ROMS partition label may differ slightly
- Both use balenaEtcher or Raspberry Pi Imager for flashing
- First boot takes 3–5 minutes to expand the filesystem