I made an IOS app for transmitting Morse code through the flashlight and decoding Morse code through the camera. I had the idea a while ago and didn't see any decent implementations so I decided to have a go at it. Let me know what you think!
There is also an Android app https://play.google.com/store/apps/details?id=com.wpeery.mor.... However, it is a bit less polished as it was the one I ended up making first. I may go back and update it to be more inline with the IOS app if I get the time.