Millions of Linux desktop users. Unlike many of the Billion Windows 10 Users it was mostly a choice. There are maybe about 100 million users of latest MacOS, it's not important to Apple profits compared to iOS products and Apple Services. Linux is not Unix, it's inspired by UNIX and uses GNU applications and tools developed originally for UNIX or BSD.
Android uses the Linux Kernel, but the Application environment is based on Java and the JVM and the GUI layer was written for Android. Google bought it in. It wasn't their design originally.
The main variations are based on Debian (Ubuntu, Mint), Red Hat (Fedora, Centos), Arch Linux and Suse. Most have good support for ARM and some other CPUs as well as x86-64 and x86-32.
Many TVs and ereaders run Linux or Android
Most embedded systems such as routers and airpoints run Linux. Microsoft uses a lot of Linux for Azure and their routers.
Most Cloud Computing and Web Servers run Linux. There are now ARM based servers though most are still x86-64.
There are three main versions of BSD, which is a UNIX predating Linux. MacOS X is from the NextStep project which was based on BSD. Mac OS9 and earlier were not Unix based.
See also OSes for the Raspberry Pi, a small computer based on an ARM phone chip.
https://en.wikipedia.org/wiki/Raspbe...rating_systems
The x86 (Intel AMD) is pretty much only used in desktops inc laptops and Servers. Most of MS Windows is now only the desktop.
More ARM chips ship in a week than AMD + Intel x86-64 in a year and most run at least the Linux Kernel unless very low end.
iOS was based on Mac OS X, so also is a Unix like OS.