TripAdvisor takes search engine optimization (SEO) so seriously that the site has its own SEO University, and it shows in its site. It loads pretty quickly on mobile with a 61/100 on Google’s mobile page speed tool, but the real strength as far as the mobile-first index goes is the content it has that addresses micro moments and near-me searches. And it is aggressively optimizing for these queries that Google said doubled from 2014-2015. TripAdvisor might want to think about the large text footers that it puts on its desktop site to optimize for these queries that do not exist on its mobile site, as the power of those will likely be neutered once the mobile site is used as the primary source for indexing and ranking signals. Get the full story at the Mobile Marketer Read also "FAQ: All about the Google mobile-first index" at Search Engine Land