# Outdoor Entrance Panels : Weather-resistant stations featuring buttons or directories, cameras, and keyless entry readers (RFID, PIN, or Bluetooth).
# Indoor Monitor Panels : Wall-mounted or desk-standing LCD screens (often 7 to 10 inches) that display the visitor and house the unlock button.
# Mobile App Integration : Many advanced setups let residents receive bell rings, view video feeds, and unlock the door remotely using their smartphones.