The units are for the most VOS (Voice Activated) and have a quality and sensitivity control accessible via the App ONLY!) These audio recording devices require an App because they connect to the internet, you can listen to the recordings via the App and will require a SD memory card (sold separate), to connect the unit you must be at the location where you will leave the unit and you will require to know the SSID and password of your internet there, and can only be hooked up to a 2.4Ghz frequency. You will need to have all the permissions and location services turned "ON" on your phone including Bluetooth.