Transponder

Censorship-resistant short messaging built on the Ethereum blockchain, built and demoed at ETHWaterloo 2017.

The app relies upon this simple Solidity contract:

pragma solidity ^0.4.15;

contract Transponder {
  address public owner;

  event Squawk(address indexed _author, string _text);

  function Transponder() {
    owner = msg.sender;
  }

  function squawk(string _text) {
    Squawk(msg.sender, _text);
  }
}