Apps that might be fun to use in a freeform. Not apps that have been written for freeforms specifically, but other apps that might be of interest to freeform writers.
This app turns your smartphone or tablet into an Enigma device (one of three models). With a couple of these apps you can sent undetectable settings to each other. You don’t even need to worry about “unauthorised” personal copies of the app being in the game, as the app is extremely configurable.
The photo to the right is the Android app. There are several iOS apps. I have no idea if they are all compatible with one another.