One more help from my side ,my experience . I am submitting this which may be helpful to you and others. You can connect an external small SPEAKER which you can connect by Bluetooth or a cable with camera phone. Supply electricity power along with mobile phone. This way you can speak to the patient(the viewed ) from wherever you are, I mean before you reach to the patient(the viewed ). You can assure the patient (the viewed )by SPEAKING REMOTELY that you are reaching there soon. That will be very helpful for a patient(the viewed ) in distress and to you also to avoid fret.–Dr Pancholi, M.D.(Ayurved),Ph.D.,MBA(HospMgmt),India. PS; A big speaker will scare the intruder who can not immediately know from where the voice is coming.And before finding out the source of voice/speaker sure he will flew.Bravo !!