Make your cheap Amazon LED lights glow with whatever's on your Mac screen.
Bought a Bluetooth LED strip or light bar and control it with a phone app? Lantern puts it in your Mac's menu bar instead: the light follows your screen like a Philips Hue setup, and you can pick any colour, a warm or cool white, or a rainbow effect. No hub, no account, no subscription.
The toad (bottom right) shows how it decides: the light matched the green background, not the toad, because that covers the most of the screen.
Website · Download · macOS 14+
Probably, if you control them with one of these phone apps:
- Lotus Lantern
- Lotus Lamp X
- duoCo Strip
- Magic Lantern
These lights are sold under dozens of brand names on Amazon, AliExpress and Temu, but inside they're the same, so the app is the best clue.
Quick check: turn the light on, then open Bluetooth settings on your Mac. If you see a device called ELK-BLEDOM or MELK- followed by letters, Lantern will work with it.
Close the phone app first; the light only listens to one controller at a time.
Tested on a MELK-OA10 light bar. Got a different one working (or not)? Tell me which and I'll add it to the list.
Have you ever bought an inexpensive LED bar, set it up behind your desk, and wished it could follow your screen the way a Philips Hue setup does?
I wanted that feature without paying for the whole Hue ecosystem. Screen sync with Hue needs Hue lights, a Hue Bridge and the Hue Sync app, which comes to about A$550 in Australia. Instead, I bought the cheapest Bluetooth light bar I could find, for A$49, and decided to solve the problem myself.
The bar came with a phone app and a remote, but it had no way to talk to my Mac. I worked out the commands it understands over Bluetooth and wrote the missing piece. Lantern runs in the Mac menu bar and controls the light directly, so there is no hub, no account and no cloud service involved. The result is the expensive feature, running on a light that cost A$49.
| Hue screen sync | This setup | |
|---|---|---|
| Light | Hue Play gradient light tube, A$419.95 | MELK LED bar, A$49 |
| Hub | Hue Bridge, A$129.95 | none |
| Software | Hue Sync | Lantern, free |
| Total | ≈ A$550 | A$49 |
The Hue prices are Philips' Australian list prices for the light tube and the bridge, checked in October 2026. To be fair to Hue, its gradient tube does more than my bar: it can show several colours along its length at once. My setup does the one thing I wanted, for less than a tenth of the cost.
The bar following the screen. Full video on the website.
| Screen Sync | Reads a tiny copy of your screen 30 times a second and sets the light to the colour covering the most of it. Black and greys compete too, so a dark scene dims the bar, and a strong colour (a red sign in a dark film) still wins over black. A Flow mode cycles through the screen's top ten colours instead. |
| Colour | A colour wheel, quick swatches, and an eyedropper that grabs any pixel on any screen. |
| White | A warmth scale from 2700K to 6500K with presets, and a tint control, because every RGB strip mixes white a little differently. |
| Effects | The bar's own flowing rainbow (both directions), plus Spectrum: the whole bar gliding around the colour wheel. |
| Calibrate | Screen colours look pastel on LEDs. Pick a colour (wheel, swatch or eyedropper), compare it with the bar, and adjust saturation, gamma and red/green/blue balance until they match. Settings are saved. |
It is built with SwiftUI and follows the macOS look: the menu bar panel uses the system's translucent glass material, so it picks up the colours behind it, and the app follows your accent colour and dark mode.
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| Menu bar panel | Screen Sync | Colour | Effects |
Screen Sync uses macOS screen capture at 96×54 pixels. Each frame is reduced to a handful of colours in memory and discarded; nothing is saved, and nothing leaves your Mac apart from colour commands to the light over Bluetooth. macOS asks for Bluetooth and Screen Recording permission the first time.
Download Lantern-<version>.zip from Releases, unzip it, and move Lantern.app to Applications.
The app is not notarized (it is ad-hoc signed, without an Apple Developer account), so the first time you open it macOS will say it can't check it. Open System Settings › Privacy & Security, scroll down, and click Open Anyway. If you'd rather not, build it yourself (below).
Needs the Xcode command line tools (no Xcode project):
git clone https://github.com/Mayukh-D/lantern.git
cd lantern
./build.sh # builds, signs ad hoc, installs to ~/Applications/Lantern.appscripts/package.sh 1.0 builds the release zip.
Rebuilding changes the app's signature, so macOS may ask for Screen Recording permission again after each build.
These lights take 9-byte frames written to characteristic FFF3 of service FFF0 (write without response):
| Command | Bytes |
|---|---|
| Colour | 7E 07 05 03 RR GG BB 10 EF |
| Brightness (0–100) | 7E 04 01 BB FF FF FF 00 EF |
| Power on / off | 7E 04 04 01 FF FF FF 00 EF / 7E 04 04 00 00 00 FF 00 EF |
| Built-in effect | 7E 00 03 CC 03 00 00 00 EF |
| Effect speed (0–100) | 7E 00 02 SS 00 00 00 00 EF |
On the MELK-OA10, effect 0x01 is a flowing rainbow and 0x02 the same in reverse. The standard ELK-BLEDOM codes (0x87–0x9C: jumps, crossfades, blinks) also work. The light only accepts a few writes in flight, so Lantern waits for peripheralIsReady(toSendWriteWithoutResponse:) before sending the newest colour rather than letting writes drop.
MIT. Not affiliated with the makers of the light or its app.