What is the Multi-touch Tester application, how does it work?

According to the introduction of Defiant Technologies, LLC, Multi-touch Tester is a Tools app on the Android platform. There is currently a 1.8 version released on Dec 21, 2015, you can see the details below.

A simple app that lets you test the multi-touch capabilities of your device's display. Draws dots on the screen that move along as you touch the screen. Test how many fingers the device can detect at the same time.