While it is technically possible to use a smartphone running an operating system other than Apple’s iOS or Google’s Android (Tizen, LineageOS, /e/ anyone?), the likelihood that you’re doing so is infinitesimally small. The majority of us are locked in a duopoly when it comes to mobile operating system choice. That’s not necessarily a bad thing: This two-way competition has pushed Apple and Google to create polished, feature-packed, and technologically potent phone software.