Mobile usability refers to the ease with which users can interact with a website on a mobile device. In Google Search Console, the Mobile Usability report shows you any issues that Google has detected with your site’s mobile usability, based on Google’s analysis of the pages on your site. This can include issues such as text that is too small to read, links that are too close together, and content that is wider than the screen. Fixing these issues can help improve the user experience for people visiting your site on a mobile device, which can in turn help improve your site’s ranking in Google’s search results.