LED Banner: Scrolling Text on Your Phone
Type a message and play it full screen in big scrolling letters. Nothing to install, and your message never leaves your browser.
How to use the phone LED banner
- Type up to 60 characters, or tap one of the saved messages.
- Pick the motion, text size, speed and colors. The preview updates as you go.
- Tap Play full screen and hold your phone sideways. Tap the screen to bring up Close, or press Esc on a computer.
| Motion | Good for | How it looks |
|---|---|---|
| Scroll | Longer messages, names, cheers | Enters on the right and leaves on the left |
| Blink | Short words (Over here, TAXI) | Flashes in place, easy to spot from afar |
| Still | One or two words, photos | Shrinks to fit and stays centered |
Ideas for using it
- Cheering at concerts and games with an artist’s or player’s name
- Airport and train station pickups instead of a paper name sign
- Birthdays, proposals and party photos
- Hailing a taxi, or getting a message across in a loud place without shouting
- A quick sign at a market stall, a booth or a group meeting point
Colors that read from far away
Contrast compares the brightness of the text and the background with the WCAG formula, from 1:1 to 21:1. WCAG 2.2 asks for at least 4.5:1 for normal text and 3:1 for large text. The banner warns you below 2:1. Light letters on a dark background read best, and there the letters get a soft LED glow.
| Text / background | Contrast | Readability |
|---|---|---|
| Yellow / Black | 14.5 : 1 | Good |
| White / Black | 21 : 1 | Good |
| Green / Black | 9.2 : 1 | Good |
| Red / Black | 5.7 : 1 | Good |
| Charcoal / Yellow | 11.4 : 1 | Good |
| White / Blue | 3.7 : 1 | Large text only |
| White / Red | 3.7 : 1 | Large text only |
| Yellow / White | 1.4 : 1 | Hard to read |
iPhone and Android
On Android Chrome the banner goes full screen and locks to landscape. iPhone Safari doesn’t let web pages go full screen, so the banner covers the page and is drawn rotated 90°: turn the phone to the left and it reads like a landscape sign. While it plays, the screen is kept awake wherever the browser allows it.
- Turn the screen brightness up in daylight or bright venues.
- Scroll speed scales with the screen height, so the small preview and full screen move at the same pace.
- Your message and settings are saved only in this browser. They are never sent to a server or added to share links.
Sources
Frequently asked questions
How do I turn my phone into an LED sign?
Type your message on this page, tap Play full screen and hold the phone sideways. Big letters scroll across the whole screen, and no app is needed.
Can I stop the text from scrolling?
Yes. Choose Still and the text shrinks to fit and stays centered, or choose Blink to flash it in place.
Does it work on iPhone?
Yes. iPhone Safari doesn't let web pages go full screen, so the banner covers the page and is drawn rotated. Hold the phone turned to the left.
Which colors are easiest to read at a concert?
White on black gives the highest contrast, and yellow on black is also far above the WCAG minimum. The banner warns you when text and background are too similar.
Is my message saved or shared?
It's saved only in this browser so it's there next time. It is never sent to a server or added to share links.