What does the negative number by my sensor mean in the mobile app?

This negative number tells you the strength of the WIFI signal your sensor is receiving in its current location. The negative number you see here can be interpreted as follows: 

-1 to -50: Excellent WiFi signal
-50 to -60: Good signal
-60 to -70: Fair signal, connection issues in this range are rare
-70 to -80: Weak signal, but still acceptable in most cases (may lead to occasional offline notifications)
-80 and below: Very weak signal, connection issues may occur more frequently

To provide some background, each of your installed sensors is displayed on the Sensors screen in the app with some important information:

• Location name (e.g. "Home" or "Vacation Home")
• Description name (e.g. "Sump Pump" or "Water Heater")
• Leak or Freeze icon (will only appear if there is an ongoing leak or freeze at the moment)
• Battery Level icon
• Battery Level percentage
• WIFI Signal Strength icon (2 bars or better is generally acceptable signal strength)
• WIFI Signal Strength value (this is the negative number next to the WIFI symbol for your sensor)

Important: The closer this WIFI signal strength value is to zero, the better the signal will be for your sensor. For example, a signal strength value of -40 is better than a strength-50. In most cases this value will fall between -30 and -90.

Note: If you do not see the signal strength number (or the WiFi symbol) next to any of your sensors, try quitting and reopening the mobile app to refresh the data.