gnome-mousetrap software package provides Head tracked mouse control, you can install in your Debian 9 (Stretch) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install gnome-mousetrap
gnome-mousetrap is installed in your system.
Make ensure the gnome-mousetrap package were installed using the commands given below,
$ sudo dpkg-query -l | grep gnome-mousetrap *
You will get with gnome-mousetrap package name, version, architecture and description in a table
| Distro | Debian 9 stretch |
| Section | GNOME |
| Package | gnome-mousetrap |
| Version | 3.17.3-3 |
| Description | Head tracked mouse control |
| Sub Section | gnome |