Arn0 Launcher

A quieter home screen for a Samsung Tizen TV: a clock, a row of your apps, a row of your consoles, and nothing else.

The browser preview, with the bundled Manrope font and the "Milky Way" wallpaper.

I built this for one TV in my living room, a Samsung Q70B on Tizen 6.5, because its own home screen had become a shop. It does what I want: the apps I use, the consoles I own, driven by the normal remote. I am sharing it as a starting point rather than a product.

Use it at your own risk. The optional Home-button setup changes TV preferences that Samsung does not document. See the setup guide before using it.

I highly recommend forking it and building on top of it, ideally with a coding agent that can help you understand and adapt the setup. Start with the browser preview, make the interface your own, then work through TV installation when you're ready. Native Home/startup changes need particular care; the setup guide covers the risks and recovery steps.

Needs Node.js 20 or newer. Nothing is installed and no TV is involved.

git clone https://github.com/<you>/arn0-tv.git
cd arn0-tv
npm run preview        # http://localhost:8080

Navigate with the arrow keys and Enter; Esc or Backspace is Back; R G Y B are the remote's colour keys. #all and #lab in the URL open those screens directly.

The preview runs against src/js/tizen-mock.js, a stand-in for the Tizen APIs that is inert on the TV itself. So the layout, focus behaviour, settings, fonts and wallpapers are all real, while launching apps and switching HDMI inputs only do something on a real TV.

Everything in src/js/config.js is meant to be edited: which apps appear, which consoles and on which HDMI ports, how an input tile switches the TV, the locale, the starting wallpaper. Most of it is also editable from the launcher's own Settings once it is on the TV, and the TV's copy wins (config.js only supplies the defaults).

Beyond config: tile colours and brand marks in src/js/brands.js, the whole look in src/css/style.css, and your own photos as wallpapers.

Anything specific to your own TV — weather coordinates, a devlog address — belongs in src/js/config.local.js instead. That file is gitignored and merged over config.js one level deep, so the tracked file keeps its nulls while the local one reaches both the browser preview and the packaged .wgt. Nothing to strip before a push, nothing to restore before a build. Copy config.local.example.js to start.

This project was largely built with coding agents, and adapting it is a reasonable thing to hand to one. A starting prompt that keeps the agent on the safe side of the line:

This is a Tizen TV launcher (see README.md). Work in the browser preview only.

Do: edit src/js/config.js, src/js/brands.js and src/css/style.css; run `npm run preview`
and check the result; keep the 1920x1080 stage and remote-only navigation intact.

Do not: connect to a TV, run sdb, sign or install a package, or touch anything
under native/. Do not change Home or startup behaviour.

TV work is different in kind: it needs a machine on the same network as the TV, so an agent that can only read this repo cannot operate the TV. This repository includes the guarded helper source, but does not include a ready-to-run SDB staging/runner script or a per-TV recovery snapshot.

docs/setup-tv.md — installing the package, then optionally the Home button and power-on changes, with the recovery steps for each.

Installing the launcher is reversible by uninstalling it. The Home-button change is reversible with the saved per-device baseline, but it rewrites undocumented platform preferences. The launcher works fine without that change, open it from the app list like any other app.

Evidence and limits:

npm run preview      # browser preview on :8080
npm run build        # -> dist/arn0-launcher.wgt
npm run devlog       # receive Lab logs from the TV into logs/tv.jsonl
node scripts/prepare-wallpapers.mjs <folder>   # regenerate wallpapers from your photos

Hidden shortcuts: Red = All apps, Green = next wallpaper, Yellow (in All apps) = show system apps, Blue = Lab. On Home, Left and Right alternating three times (◀ ▶ ◀ ▶ ◀ ▶) starts the hidden game; OK / Up jumps, Down ducks, Back returns Home. The code alternates rather than repeating a key because a held remote key auto-repeats, which would both break a run-based code and fire it by accident while sweeping along a row.

src/                  everything that goes into the .wgt
  config.xml          Tizen manifest (app id, privileges)
  css/style.css       1920x1080 stage; performance rules measured, not assumed (see its header)
  fonts/              Manrope, Inter, Outfit, DM Sans (OFL), bundled so nothing loads from the network
  img/marks/          brand marks (Simple Icons CC0, Custom Brand Icons MIT; see SOURCES.md)
  img/tiles/          marks recoloured per brand (generated at build)
  img/wallpapers/     1920x1080 wallpapers with the readability scrim baked in (generated)
  js/config.js        your apps, consoles, HDMI method, locale, theme
  js/config.local.js  gitignored per-TV overrides, merged over config.js (not in the repo)
  js/brands.js        tile colours and marks per brand
  js/apps.js          list / filter / launch via tizen.application
  js/inputs.js        HDMI via tizen.systeminfo + tizen.tvwindow
  js/wallpaper.js     wallpaper display and rotation
  js/screensaver.js   idle screen saver: photos, slow zoom, clock
  js/appearance.js    clock, date and font settings
  js/weather.js       Open-Meteo reading for the screen saver corner
  js/prefs.js         settings saved on the TV
  js/ui.js            screens, focus, keys, toast, pop-up menu
  js/home.js          Home, All apps, Lab
  js/settings.js      Settings pages
  js/devlog.js        development log (Lab screen, optional upload to your computer)
  js/render-probe.js  measures what this TV can actually render (Lab screen only)
  js/platform-probe.js  reports which tizen.* / webapis.* APIs the TV exposes (Lab screen only)
  js/boot.js          start-up
  js/tizen-mock.js    fake Tizen APIs for the browser preview (inactive on the TV)
scripts/              build.sh, serve.mjs, devlog-server.mjs, fetch-assets.mjs, make-icon.mjs
native/               guarded Home/startup helpers — read docs/setup-tv.md first
docs/                 setup guide

Saved on the TV in localStorage. They survive restarts and in-place updates, not an uninstall.

• Background — Off (plain gradient), one photo, or rotate: on each Home, 30 s, 5 min, 15 min, 1 hour, daily.
• Apps on Home — OK on an app opens Move / Remove; OK on the right-hand slot adds one.
• Consoles — per console: rename (on-screen keyboard), HDMI port, logo, how it opens, hide, reorder, remove; plus add a console.
• Appearance — 24/12-hour clock, date shown/hidden, date language (English, Español, Français), font, app names (always / when selected / never).
• Navigation sound — turn arrow-key sounds on or off, choose Soft, Warm or Bright, and preview the selected tone.
• Screen saver — on or off, start after 3/5/10/15 min idle on Home, photo change every 60/75/90 s while Background is on Rotate, go dark after 30 min / 1 hour / 2 hours / never, and show it now.
• Samsung Home — opens com.samsung.tv.csfs, from which TV settings are one press away. Opening com.samsung.tv.coba.setting directly does not work on this TV. Keep this entry: it is the route back if you have redirected the Home button.
• Advanced — refresh the app list, export settings to the log, reset everything, Lab.

Photos are cropped to 1920x1080 and darkened (top-left for the clock, bottom for the tiles) at build time, so the TV only ever draws one plain JPEG on its own layer. Drop photos in a folder and run node scripts/prepare-wallpapers.mjs <folder>; friendly names and crop positions for known files live in that script. Current photos are from Unsplash; credits appear when you switch with Green.

After a few minutes with no input on Home it shows the wallpapers full screen with the clock, the weather and the photo's name in the corners. Any button closes it, and that press does nothing else. It never appears over a console input, another screen or the hidden game.

The weather is off until you put coordinates in config.local.js (see What you can change). It comes from Open-Meteo, which needs no API key, and there is deliberately no Settings page for it: the TV does not move, and coordinates are not something you type with a remote. The reading is cached in localStorage so the screen saver opens with real numbers even after the TV has been off, it refreshes at most once an hour and only when something is about to show it, and anything older than three hours is treated as no reading at all — an unattended screen should go blank rather than state yesterday's temperature as if it were now.

Everything in it moves, because a clock parked in one corner for an hour is a burn-in risk: the photo drifts across 320 px while it is up and the next one drifts back the other way, the corner text shifts a few pixels on each photo change, the clock moves to another corner every two and a half minutes, and the whole thing fades to black once the configured hour is up. Photos follow the Background setting — Rotate cycles them, a single photo is held, Off leaves just the clock — using the screen saver's own position, so it never rewrites the wallpaper Home comes back to.

Black, rather than off, because a web app cannot turn this panel off: tizen.power and webapis.power are both absent on the reference TV, which Platform probe: what APIs this TV exposes in the Lab screen will confirm on yours. No privilege changes that — an absent API gives you nothing to be refused by. A real power-off is the TV's own Eco Solution ▸ Auto Power Off, driven by the same absence of remote input that started the screen saver.

Only transform and opacity animate, which the compositor can run without repainting. Not every composited property is equal here, though, and only running it on the TV showed it: the first version used a slow scale(), which this engine re-rasterises in visible steps rather than compositing, and it stepped badly enough to be unpleasant to watch. A translate() of the same layer is smooth, so the photo pans instead of zooming and the layer is laid out 320×180 larger than the screen to give it room. The Lab probe cannot settle this one: it times a JavaScript repaint loop, and a transition that runs off the main thread reads as a clean 60 fps there whether or not the panel keeps up. Judge it by eye on the TV.

getAppsInfo reports many internal services as visible, so All apps keeps only ids that look like store apps (AbCdEfGhIj.Name, or numeric) plus a short list of preinstalled consumer apps, and drops names containing service/worker/agent/e-manual. Yellow shows everything when you need to find something. The id of the focused app is shown bottom-left — pin it in config.js as { id: '...' }, which is more reliable than a name match.

tizen.systeminfo.getPropertyValue('VIDEOSOURCE') lists the ports and tizen.tvwindow.setSource() changes the source (privilege tv.window, public). What happens next is undocumented, so inputMethod has three options:

• switch+viewer (default) — set the source, then open Samsung's TV viewer, so the console is shown by the TV itself with Game Mode and friends as usual.
• switch — only set the source.
• inapp — show the input full screen inside the launcher; Back returns to the dashboard. Probably no automatic Game Mode or VRR this way.

The Lab screen (Blue) tries each method per console and reports what happened. The dot on each tile is green when the TV reports that port as connected.

To collect Lab results on your computer, point devLogUrl in config.js at it and run npm run devlog; entries land in logs/tv.jsonl. Set it to null to disable, which is the sensible setting for a TV you are not actively debugging.

The TV will not tell you what it can render, so the Lab screen measures it. Render probe: everything walks a focus ring along eight tiles — the same work as moving along the apps row — and counts frames against the wall clock for each of four stages. Results land in the log.

On the reference Q70B (Chromium 85, 4 cores, 2 GB), baseline is 59.5 fps / 16.8 ms with no dropped frames, and:

So soft shadows are fine and background glows are not. Bake a gradient into the wallpaper at build time instead — scripts/prepare-wallpapers.mjs already does exactly this for the readability scrim.

The probe also reports the engine and its CSS support, which saves guessing: Chromium 85 has grid, gap, sticky and clamp(), but no inset, aspect-ratio, overflow: clip, individual transform properties, color-mix(), container queries or :has().

Re-run it on your own TV before trusting any of these numbers; that is the whole point of it. Two of my own early runs produced nonsense — requestAnimationFrame on this engine stops tracking vsync and fires callbacks in batches, which reads as absurdly high frame rates, so the probe now measures against Date.now() and flags any sample faster than the panel refreshes.

Forks and experiments are welcome. If you report a problem, include your model, firmware and what you actually observed, and strip local addresses and device identifiers first.

What I would find most useful: results from other models and Tizen versions, and especially from a TV where db/menu/smart_hub/ontvsetting/auto_start starts at 0.

MIT for the original code and documentation — see LICENSE. Bundled fonts (OFL), Unsplash photos and brand marks keep their own terms. Weather data by Open-Meteo, used under its non-commercial licence. Brand names and logos belong to their owners.

This project is independent and is not affiliated with Samsung or any streaming service.

The Home-button approach follows CleanFrame, which documented the method on a 2024 Frame. The guarded helpers here are an adaptation tested on the Q70B and exact firmware listed above; that does not establish compatibility with other devices.