Crowd Light Show is a free, open-source web app that turns a crowd's phones into one light show synchronized to the music.
The show flashes bright light. People with photosensitive epilepsy or sensitivity to flashing light should not take part. Flash rate is capped to no more than 3 flashes per second and large saturated-red strobing is blocked (per WCAG 2.3.1/2.3.2), but please use judgement. You can leave any time with the “Stop” button.
Taking part in a show is anonymous — no account, no name, no email, and the join/show page sets no analytics cookies. If you enable the flashlight on Android, the browser asks for camera permission because that is how the web exposes the LED; no image is ever opened, recorded or sent — the camera is used only to switch the light on and off. Session data is discarded when the show ends. The marketing website itself uses Google Analytics only if you accept the cookie banner — see the privacy notice for details.
Licensed under Apache-2.0. Source: github.com/AndriiShramko/crowd-light-show. You're free to use, run and modify it.
Free for any use. Want it customized, integrated, supported, or extended for your event/venue? Contact Andrii Shramko — LinkedIn · zmei116@gmail.com · book a call. Let's talk.
Music licensing for public performance is the organizer's responsibility (in Poland: ZAiKS and related societies).
Tell us a little about your event and we’ll get you set up — or get you a quote for managed work.
Got it — we’ll get back to you within one business day. Talk soon!
Open the live demo together: it’s a synced light show you can share. Send this link and watch your phones light up as one.