As with mobile phone,press the button,you can easily open two-way intercom, whenever and wherever possible to remote visual communication. Independent research and developmenet of proprietary software. WiFi:Color,smooth video not cotton. The network camera external wireless antenna,wire bound save,make installation easier. Multi stream:The C7838WIP camera can also output 720P,VGA,QVGA three kinds of stream.If you would like to view by your smart phone.Machine 3G network remote viewing,can choose QVGA stream flow,more province. If you are using WiFi network can be selected 720P,VGA stream,more hd.