GalaxyHz — Force 120 / 96 / 60 Hz & more on Samsung Galaxy devices

A Material 3 Expressive root app + Magisk module that forces any refresh rate your panel supports — 120 Hz, 96 Hz, 60 Hz, even the hidden intermediate HS clocks (100 / 104 / 110 / 112 Hz) — on Samsung Galaxy phones running AOSP-based ROMs (Evolution X, LineageOS, crDroid…) that lack Samsung's One UI refresh-rate service.

Panel modes are discovered at runtime from the device's own mode table (/sys/.../panel/display_mode), so the app adapts to your exact hardware instead of hardcoding one phone. Verified live on a Galaxy S20 (SM-G981B, x1s) on Evolution X / Android 16: SurfaceFlinger reports renderRate=120.00 Hz with the panel locked in the HS clock region — no more mid-frame desync, sparkle or static.

Quick download (no release page needed)

• App: apk/GalaxyHz_v2.3.apk — install directly
• Magisk module: MagiskModule/ — the module unzipped and browsable: read every script on GitHub (module.prop, service.sh, common/force_120hz.sh…), or download the ready-to-flash force_120hz_x1s.zip. To rebuild the zip yourself: zip the contents of MagiskModule/ (module.prop must sit at the zip root).

💡 If the screen shows sparkle/static after a rate change: sleep and wake the phone once — the panel re-initializes and it clears. Details in Troubleshooting.

Screens

Home — live FPS, three main modes, quick lock	Resolution — FHD+ / WQHD+ switching
Custom rate — 24–240 Hz slider (frame-paced)	Adaptive — fixed / stock / custom range
Experimental — hidden HS panel modes	Tools — verified lock, AOD, DDI reset

A modal navigation drawer (hamburger menu) holds everything, plus a Quick Settings tile that cycles 120 → 96 → 60 Hz and three home-screen widgets:

Widget	What it does
Rate (4×1)	Direct 60 / 96 / 120 buttons + big live rate readout that cycles on tap
Cycle (1×1)	Shows the live rate; one tap cycles 120 → 96 → 60
FIX (1×1)	One tap runs the verified anti-flicker lock (idle timer 0, content detection off)

The launcher ships a custom adaptive icon (speedometer + Hz bolt).

The live FPS readout never sits at 0: it comes from DisplayManager, and when that returns nothing the app falls back to SurfaceFlinger's real render rate over root.

Features

Modes

• One-tap panel modes — every primary mode your driver exposes (S20: 120HS / 96HS / 60NS), each written through four layers so it sticks:
  1. cmd display set-user-preferred-display-mode (DisplayManager / SurfaceFlinger)
  2. settings put system|secure|global ... (framework refresh policy)
  3. wm size (render resolution)
  4. echo <index> > .../panel/display_mode (direct panel driver write, index resolved at runtime from the device's mode table)
• Custom rate (24–240 Hz slider) — Android advertises any 0.1 Hz-step rate to apps while the panel scans at its nearest real clock, with frame pacing in between. Great for 24 fps video (24/48 Hz) or fine battery tuning.
• Hidden / experimental modes — panels ship with intermediate HS clocks Samsung never exposed (S20: 100/104/110/112 Hz). The app lists what your driver reports and writes them directly, then reads back whether the panel took the mode.
• Resolution switching — FHD+ ↔ WQHD+ on panels that support both, with auto-scaled density so the UI keeps the same physical size — plus a manual density stepper (±10 dpi and one-tap Auto) in the Resolution screen.

Adaptive behavior

• Fixed — kills SurfaceFlinger idle/content detection: the anti-flicker default. The app verifies the result by reading back props and settings and shows exactly which layer failed, instead of pretending it worked.
• Adaptive (stock) — restores content detection for battery saving.
• Adaptive with custom range — the system adapts but stays inside a min/max you choose (e.g. 60–120 Hz, or 96–96 to emulate a fixed rate).

Flicker protection & recovery

• Lock refresh rate (apply + verify) — idle timer 0, content detection off, min = peak; each layer checked and reported.
• AOD toggle — Always-On Display runs the panel in its 60 Hz/AID clock region and is the main flicker source on S20 OLED; toggle it safely from the app.
• Emergency DDI reset — power-cycles the display controller; clears static, sparkle and glitch bands instantly.

Setup & polish

• First-run setup wizard — explains what the app does, offers a direct shortcut to Magisk for the superuser prompt, and can be skipped for non-root status reading.
• Language setting — English base with French built in; switching applies instantly, no app restart.
• Developer overlay toggle — the same "show refresh rate" overlay as Developer options, switchable from the app to verify modes really stick.
• Module zip export — copies the installed Magisk module's zip to Download so you can inspect or re-flash it from any file manager.
• Real Material 3 Expressive — material3 1.5.0-alpha with ExperimentalMaterial3ExpressiveApi: MotionScheme.expressive() spring physics, LoadingIndicator, expressive shapes (rounded, cut-corner burst, scalloped cookie), gradient accent washes, animated FPS bar and pulsing glow ring, drawer-based navigation.

The truth about "overclocking" phone panels

Phone DDICs (display controllers) ship with a fixed mode table burned in at the factory. Unlike PC monitors, there is no free-running pixel clock: a mode that is not in the table physically cannot scan out. What is possible — and what this app does — is use every mode already in the table, including the hidden intermediate HS clocks Samsung never exposed in settings. If a mode is rejected, the panel simply ignores the write; nothing breaks.

Requirements

• Samsung Galaxy with a panel_drv sysfs interface (S20 / S20+ / S20 Ultra / Note 10+ family verified; other Samsung models work through runtime discovery).
• Root with Magisk.
• An AOSP-based ROM (One UI already manages rates natively).

Files in this repo

Path	What
apk/GalaxyHz_v2.3.apk	Latest APK, directly downloadable without going through the Releases page
MagiskModule/	The Magisk module unzipped and browsable — read every script, or zip the folder to rebuild force_120hz_x1s.zip
app/	App source (Kotlin + Compose)

If the screen flickers after changing the rate

Lock and unlock the phone once (power button off → on). The panel re-initializes and the sparkle/static/bands clear. This is a panel-level quirk of HS↔NS clock transitions on S20 OLEDs, not a bug in the app or module — the module's DDI reset button (app: Tools → Reset display panel) does the same thing in software.

Also make sure only one tuner app controls the display: two root apps fighting over refresh rates (e.g. GalaxyHz + another "S20 Tuner" app) makes both unreliable.

Install

App

adb install GalaxyHz_v2.2.apk

First launch shows the setup wizard; grant the Magisk superuser prompt when it appears.

Module

Flash force_120hz_x1s.zip in the Magisk app (Modules → Install from storage), or:

adb push force_120hz_x1s.zip /sdcard/Download/
su -c "magisk --install-module /sdcard/Download/force_120hz_x1s.zip"

Reboot. The module re-applies the persisted mode at every boot, applies anti-flicker props early, and adds an Action button in the Magisk app for on-demand re-apply.

Module config — /data/adb/force_hz.conf:

120              # 120 Hz FHD+
96               # 96 Hz FHD+
60 1440x3200     # 60 Hz WQHD+
120 dpi 560      # manual density override (otherwise auto-scaled per resolution)

Building

./gradlew assembleDebug        # APK in app/build/outputs/apk/debug/
./gradlew testDebugUnitTest    # unit tests (panel-table parser, CI runs these)

Requires JDK 17+ and the Android SDK (API 36). CI (GitHub Actions) builds and tests every push.

Troubleshooting

Symptom	Fix
Screen static / sparkle after a while	Tools → Lock refresh rate (verified), disable AOD
Glitch bands mid-frame	Tools → Reset DDI; screen blinks once and clears
Rate drops after unlock	Install the Magisk module so props are set at boot
1440p after a ROM update	Home → tap any mode; wm size is re-applied
Experimental mode does nothing	Your unit rejected the mode; pick another

License

MIT — see LICENSE.