kureka

hi, i intend to install the camera near front door and I'm exploring an option of adding external speaker to IS model. Basically, when somebody is at the door I would like to speak to them. Do I need to add any alarm into the camera (e.g. connected to the bell) or does the push notification on the mobile hikvision app work well? Is the app capable of audio - two way conversation? I appreciate your advice. Thanks.