LED (Light-emitting diode) to LED communication, also known as “Mobile Device Light Communications” are sundry techniques which repurpose mobile computer devices, including mobile telephones, to communicate with other devices, using visual or infrared light. “Mobile device light communication” differs from Visual Light Communication as “mobile device light communication” transmits data at speeds thousands of times slower than Li-fi. “Mobile Device Light Communication” takes various forms: Picalico exploits the features of two iOS mobile devices. Light Message also does so for Android.