So I went to a large city Christmas concert last night and they had a song which they had the audience turn on a free app called "wham city lights" before one song. So it seemed to turn the audience and all the people using the app into a giant light show .... Changing colors based on the sounds and also using the phone flash .... Was pretty cool in a church that held around 3000 . Anyone used this in their own show? Not sure it would be effective in a small scale setting.
