At apps open you will be promted to enter your ip address for the dvr that you want to control, there is also a help me find my ip walk throught built into the app. You will need to enter that ip address each time the app runs. you need to be on the same network via wifi that your DVR is on. You can use this over 3g, but you must use your public IP address and set your router to forward port 8080 to your ip of the dvr you wish to control.

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