Reddit is a:

Reddit is a mobile-first platform because the majority of its users access the site through its mobile apps. This design philosophy prioritizes the mobile user experience, ensuring features and content are optimized for smaller screens and on-the-go consumption. While Reddit is accessible on desktop and tablet, these are secondary access points. A desktop-first platform would prioritize the larger screen experience, which is not the case for Reddit. Tablet-first and TV-first platforms are incorrect as they do not reflect the primary way users engage with Reddit.