Upgrade Your Door Phones to Be Smart with Skyboxs!!! 1. Convert Wired Analogy System into WiFi IP Intercom System 2. Apply to 2/4 Wires Villa System or Multi Apartment System 3. Control by iOS/Android Smartphones or Tablets Unclock your TCP/IP video door phone/wireless ip video door phone/digital-analog video door phone with your smartphones or tablets. You won't miss any visitors no matter where you are.