This app, and its Mac counterpart will not work correctly for external access, if you have FiOS at home. When contacting Screens support, their response is that its a hardware problem on my end. It seems their app will only work externally if you use an Apple router directly for internet access. When asked for a workflow to use a FiOS router, they just say contact Verizon and/or its a hardware problem with my router. No solutions. Not a good experience at all.