R36S Custom Firmware Compared: ArkOS vs ROCKNIX vs DarkOS vs Stock

The R36S can run several different operating systems, and choosing between them is one of the first decisions a new owner faces. This guide breaks down the real options — what each one is, which hardware it supports, and which to pick — without the forum jargon.

First: Firmware Follows the Chip

Before comparing options, the one rule that governs everything: R36S firmware is built for the chip, not the brand. Almost every R36S (and its clones like RetroSnap and GameLab) uses the Rockchip RK3326; the R36 Max and R36S Ultra use the RK3566. Any firmware you flash must match your chip. Check which one you have before doing anything — see our ArkOS install guide for how to confirm.

The Options

1. Stock Firmware (what it ships with)

Most R36S units arrive with a pre-installed EmulationStation-based OS on the bundled SD card.

• Pros: works out of the box, nothing to flash
• Cons: quality and organisation vary wildly by seller; often cluttered, sometimes with ads or junk; updates are non-existent
• Verdict: fine for trying the device, but most owners replace it

2. ArkOS (the community default)

ArkOS is the most widely-used and best-documented custom firmware for RK3326 handhelds.

• Pros: huge community, frequent updates, correct emulator cores per system, clean interface, extensive device support
• Cons: setup takes ~20 minutes; you supply your own legally-owned games
• Best for: almost everyone — it's the safe default recommendation
• Supports: RK3326 (R36S, R36S Plus, R36 Pro, R36H) and, via its RK3566 builds, the R36 Max / R36S Ultra

3. ROCKNIX (the powerful alternative)

ROCKNIX is a community Linux distribution for handheld gaming devices (the successor to the earlier JELOS project). It's already listed as an official OS option on the R36 Max and R36S Ultra.

• Pros: actively developed, strong RK3566 support, good for RetroAchievements and networked features on Wi-Fi models
• Cons: slightly steeper learning curve than ArkOS for first-timers
• Best for: RK3566 owners (R36 Max / Ultra) who want a modern, actively-maintained OS, or anyone who prefers its interface

4. DarkOS and Other Emerging Names

DarkOS is a newer name circulating in the R36S community as another custom-firmware option. As with any emerging community build, availability, device support, and update cadence are less established than ArkOS or ROCKNIX, and they vary over time.

Our honest recommendation: treat newer/less-documented firmware as experimental. If you want something that reliably works today with the largest support community behind it, ArkOS (RK3326) or ROCKNIX (RK3566) are the proven choices. If you want to try an emerging build like DarkOS, do it on a *spare SD card* so your working ArkOS/ROCKNIX setup stays intact — flashing firmware only affects the card, not the device, so experimenting is low-risk as long as you keep a known-good card.

Quick Recommendation

The Good News: You Can't Really Break It

Custom firmware on the R36S lives entirely on the SD card, not the device itself. That means:

• Flashing a new OS only rewrites the card
• Keeping your old card means you can revert instantly
• Trying multiple firmwares just means multiple SD cards

So there's no real risk in experimenting — the worst case is a card that won't boot, which you re-flash. Start with ArkOS as your daily driver, and branch out from there.

Whichever firmware you land on, your device runs the same 18,000+ game compatibility library — the OS changes the interface and features, not which games your chip can play.