3CXPhone for iPhone is an iOS VoIP client that has been specifically designed to work seamlessly with 3CX Phone System 12.5. The app allows you to use your iPhone or iPad as your office extension, meaning you see the presence and status of your colleagues and employees and calls between you are free, making you save money on your telecommunications bills. Make and receive office calls with your iPhone or iPad from anywhere in the world, setup conference calls and manage your voice mail via Wi-Fi or 3G.