Google released mobile-first indexing in March 2018. Why should you care? What steps should you take to make sure your website is mobile-first ready? Don’t wait till 2019. Start planning now and execute.
Here is the link to learn more about Google AMP pages: https://www.ampproject.org/case-studies/
Here is the Google Mobile-friendly test link: https://search.google.com/test/mobile-friendly