4level is a companion app for the 4level wireless liquid level sensor. Monitor the level in your septic tank, rainwater tank, or well from your phone—without opening the lid.
REQUIRED DEVICE: The app works with the 4level sensor (available for purchase at ghostek.pl). Without the sensor, the app won't display measurements.
KEY FEATURES:
📊 Current Level and Measurement History
Clear level graphs from the sensor's entire operating history. You can see the filling trend and a forecast for when the tank will be full.
🔔 Instant Push Alerts
Set an alarm threshold—when the level exceeds it, you'll receive a push notification with vibration. Further reminders will be sent if the level continues to rise. No more overflowing septic tanks.
📱 Home Screen Widget
The tank level is always visible on your phone's desktop—no need to open the app. The widget refreshes automatically.
🔋 Sensor Battery Status
The app displays the device's battery level and warns when it's time to replace it (a set of 4 AA batteries lasts over a year).
📧 Email Notifications
In addition to push notifications, you can enable email notifications—useful when your phone is out of range.
🏠 Home Assistant Integration
The sensor can be connected to your Home Assistant via MQTT—entities appear automatically.
HOW IT WORKS:
The 4level sensor is mounted above the tank. The millimeter-wave radar measures the level contactlessly (accuracy ±1 cm, range up to 10 m) and sends data via Wi-Fi to the cloud. The app displays measurements in real time and alerts when the threshold is exceeded.
APPLICATIONS:
• Septic tank and sewage tank—overflow alarm
• Rainwater tank—controlling water supply for irrigation
• Well—monitoring groundwater levels
• Any liquid tank
Monitor rainwater or septic tank levels. Push alerts and widgets.