Hidden cameras can be revealed with a cheap gadget that can be attached to a mobile phone

The issue of hidden cameras in accommodations is widespread, prompting Airbnb to ban indoor security cameras. Researchers from Korea and Singapore introduced a device called SweepLED at the ACM MobiSys 2026 conference, which detects hidden cameras by analyzing light reflections. Unlike traditional methods that can lead to false alarms, SweepLED uses a smartphone case with LEDs to illuminate suspicious objects from various angles while recording reflections. The system achieves about 94% detection accuracy after testing on 30 different objects, including those with built-in cameras. The components for the device are inexpensive, suggesting potential for affordable consumer use.