Way to send a signal from one android to the other?
I am trying to find a way to be able to send a signal (Will be one letter sent) from a main Arduino to a secondary mini unit. I was looking at wifi to do it but they don't work with the mini board and also they cost a lot. I tried Bluetooth but the distance is to far for it to work. I am looking at about 60ft max through 2 walls. Is there anything that would work for doing this.