The purpose of the Camera Detector app is to detect hidden cameras and recording devices in various settings such as hotel rooms, changing rooms, and public restrooms. The app uses the device's camera and sensors to scan the surroundings for any signs of hidden cameras that may be used for illicit purposes such as spying or invasion of privacy. By alerting users to the presence of these hidden devices, the Camera Detector app helps individuals protect their privacy and security in potentially vulnerable situations.