When it comes to mobile smart phones, Google and Apple have a duopoly. Much like Apple and Microsoft did/still do. There are some projects that are changing this. Making open sourced phones that allow use Linux in your pocket. I am going to go over three of the most popular, and best phones that use Linux. So that you can incorporate free and open sourced software into every facet of your life.
Note that - although people like to pretend otherwise for some reason - technically Android is a Linux based OS, so all Android devices are Linux devices. This is why apps such as Termux work.
(As the proud owner of a PinePhone I would rather have it over an Android based device, though!)
True. I think in a list of Linux Chromebook alternatives I included Android x86. Android is Linux.