Squish GUI Tester can run on a wide variety of different platforms (embedded, mobile, desktop, etc).
Here is a list of minimum supported platforms for the Squish binary packages from the download area .
Minimum Supported Platforms by Binary Packages¶
|Squish 6.7||Windows 7|
|CentOS 7 for Squish for Qt 5.8+ packages, CentOS 6 for other packages|
Debian 8 for Squish for Qt 5.8+ packages, Debian 7 for other packages
Ubuntu 16.04 for Squish for Qt 5.8+ packages, Ubuntu 14.04 for other packages
or newer versions of these distros
Please note that Squish can run on other platforms as well (embedded or older operating systems for example).
But some of its parts have to be built from the sources and the remote testing has to be used.