The TP-Link Tapo T315 Smart Temperature Humidity Monitor is an addon device that requires a hub for connectivity and utilizes the Tapo app for alerts and control. 

Key Features:

• Real-Time & Accurate Monitoring - Detects real-time temperature and humidity with great accuracy. (Measurement Accuracy: ±0.54 ºF, ±3% RH).

• 2.7" E-ink Display - Indicates temperature & humidity, comfort level with facial expressions, battery condition, and signal.

• Home Automation - Automatically turn on/off home electronics (e.g. heater, fan, humidifier and more) to maximize conformity and save energy.

• Instant App Notification - Receive app alert notification when conditions fall outside the preset range.

• Free Data Storage & Visual Graphs - Record temperature and humidity data and generate periodic data summaries.

• Flexible Installation- Just place it on the desk or mount it on the wall.

• Hub Required - The Tapo Hub is required to support smart features, like remote monitoring, home automation, data export and more.