Social media platforms for politics: A comparison of Facebook, Instagram, Twitter, YouTube, Reddit, Snapchat, and WhatsApp.

Citizens have increasingly diversified their use of social media platforms, raising questions about which platforms are adopted and for what purposes. We use survey data from four countries (Canada, France, the United States, and the United Kingdom) gathered in 2019 and 2021 (n = 12,302) about Facebook, YouTube, Instagram, Twitter, Reddit, Snapchat, and WhatsApp. Political ideology predicts the adoption and political uses of all platforms, but Reddit, Snapchat, and WhatsApp are distinctive. Right-wing users are more likely to report exposure to and posting of political content on these platforms; this pattern is consistent across all four countries. We relate these findings to the distinct network features compared to other platforms. Our large sample size allows us to document a funnel process where large numbers adopt a platform, fewer see political content, and even fewer post. In this funnel process, ideological differences become larger. The findings have implications for the formation of homogeneous communities.