Install libgrail6 by entering the following commands in the terminal:
sudo apt update sudo apt install libgrail6
Description:
Gesture Recognition And Instantiation Library
This library consists of an interface and tools for handling gesture recognition and gesture instantiation. Applications can use the grail callbacks to receive gesture primitives and raw input events from the underlying kernel device.
Homepage: https://launchpad.net/grail
Version: 3.1.0+16.04.20160125-0ubuntu2
Section: universe/libs