<![CDATA[The procedure for inspection of storage tank water levels which is still applied today has several disadvantages. One of them is the storage tank, which is often located on the roof of the house making it difficult to monitor storage tank water level. The solution to that problem includes monitoring water using a resistance wire. However, if you use a resistance wire compounds found in water can affect its value. In addition, it can also use ultrasonic sensors, because ultrasonic sensors are able to measure water levels with an average measurement error of 4.93%. This is what triggers the creation of an Android-based mobile application that is equipped with Arduino and its components to be able to monitor water level in storage tank. The Arduino device is mounted on the top of the storage tank and the HCSR04 ultrasonic sensor is facing the inside of the storage tank. The HC-SR04 ultrasonic sensor will work to calculate the water level in the storage tank, and the calculation results from the sensor will be forwarded to the mobile application via internet network. From the use of the application, the results can be shown in realtime water level with percentage and 2D images on the mobile application with good results, the percentage of compatibility between the results of manual measurement with the application is 80%. In addition, the application can provide notifications in the form of Push Notification that appears when the water level has reached the upper or lower limit.]]>
