Is the Bluetooth 4.0(Ble) backwards compatible? Is there one Bluetooth that will connect with all of them? I bought this shield http://www.seeedstudio.com/depot/bluetooth-low-energy-shield-p-1255.html?cPath=132_134 from red bear lab. It worked on the 4s but i am looking for a bluetooth that can connect to previous Bluetooth's. I read online that the 4.0 was backwards compatible but i guess not since the shield won't connect to my iPhone 4 a Bluetooth v2. Is it a programming problem or just hardware? Where can i find a Bluetooth shield for the UNO that will connect with any existing Bluetooth's?