When did Google announce its mobile-first indexing initiative and re-introduce the Mobile Friendly Testing Tool? By vmartinez When did Google announce its mobile-first indexing initiative and re-introduce the Mobile Friendly Testing Tool? December 2016 October 2016 November 2016 January 2017 Related content Related questions:Select all that apply: In order to account for…To rank search listings, the Google algorithm…Which of the following is the most important aspect…You’re setting up keyword insertion for your Search…