The Nest Doorbell has built-in intelligence and can tell the difference between a person, package, animal, and vehicles and send you an alert in the Google Home app[1], no subscription required Easily check in from anywhere 24/7 with live HD video with HDR and night vision[1]; see what you missed with 3 hours of free event video history[2]; or add a Nest Aware subscription (sold separately) for up to 60 days of event video history[3] If your Wi-Fi goes down or there’s a power outage, the Nest Doorbell will store up to 1 hour of recorded events so you can see what you missed[4]; The Nest Doorbell is easy to install wired or wire-free; the built-in battery means it works with any door, or connect it to your existing doorbell wires with the included wire connector Whether you choose battery or wired installation, the battery-powered Nest Doorbell cannot continuously record 24/7 video history, even with a Nest Aware subscription; Control Method: Application Control Method: Application