What do the colors of the app cards mean?

Once you have completed pairing the Sensor, the App will automatically generate a corresponding Sensor card.
The colors of the Sensor cards displayed on the App’s homepage have the following meanings:
• Yellow: indicates that the Sensor is online, is updating data normally, and has established effective communication with the Hub.
• Gray: indicates that the Sensor is offline, communication with the Hub has been interrupted, and the Sensor will not upload any data during this time.
• When you poke the pinhole on the Sensor with a pin, the background color of the corresponding Sensor card will blink once and automatically update with a new data reading.