Coder will develop an app where two people on Facebook can play Heads Up poker against each other. Experience should be indistinguishable from playing on a real poker site; that is, the app should respond quickly and according to the rules of poker,? and it should include support for looking at previous hand histories. Players should be rated based on the ELO formula (like chess). The applet should recommend that the player challenge people with similar skill, and list 3 logged on players that meet this criteria. The software should also let players challenge their friends. Coder is responsible for all code, graphics, and the required database back-end coding.