At the 2026 World Cup match Jordan vs Algeria, the American company CUE ran a phone flashlight show. CUE used to work through an app, and now it has also learned to control flashlights through the browser.
The comments show the usual worries: phones being hacked, and whether these are wristbands. They are flashlights, there is no hacking, and most viewers happily take part.
What we can do
GROMKA.SHOW does the same at a large scale: it controls phone flashlights via ultrasound. The technology is our own and technically different from CUE, and we are filing patents. How the sync works is in our ultrasound article.
The main difference: besides flashing we can draw seat-based pictures from flashlights and send waves across the stands. These are more complex effects than everyone flashing together.
At the Russian Cup semi-final Krylia Sovetov vs CSKA at Samara Arena there were 27,000 spectators. The floodlights there can’t be switched off instantly, so the effect was weaker than in the dark, but the technology worked, and a prize draw followed the show.
A full comparison of PixMob wristbands, CUE’s sound technology and our ultrasound is in how a crowd is synchronized. The stadium format is on the stadium pre-match show page.
