This is application is making use of the flashlight of your smartphone to do various thinks. First of all, it works as a simple flashlight with an on/off switch. But this is not the only think it does. You can make the flash to continues flashing on custom timings. And you can use it to send Morse code, by translating what you wrote to flashing. And if you don't have flash, don't worry. The same things are done by your screen.