Gobius

This app is designed to be used with the Gobius C sensor. The sensor is measuring sleeplessly from empty to full tank for all kinds of fluids. It gives you to volume in % and liters. 
The sensor is placed direct on top of the tank on plastic and glass fiber tanks. On metal tanks, you need a hole, at least 40 mm.
Gobius C is ready to use; everything is in the box. You get the sensor with a 3M tape, a Quick Guide, 3M tissue, a cable to connect to a power source (12-24 V), and to use for external devices, like warning lights/buzzers, control systems, and analog gauges. The Quick Guide gives you a brief overview of installing the sensor. And the sensor is waterproof IP66.
In the app you have everything; Installation Guide with instructions for mounting the sensor on the tank, setup/calculation and displaying the fluid level in different colors. The app has also a Tank Calculator for non-rectangular tanks, such as round and triangular tanks. Installation should take no longer than 15 minutes