Should certain text be used in the coding, to secure a higher search engine ranking on Mobile search results?
It doesn’t really matter how you code it, as long as it is clear and transparent if you are directing users to a mobile version of the page. Google will look at how well adapted your site is for mobile, in terms of bandwidth etc, and will look at whether your site adapts to different sizes, but at the end of the day you can still be ranked #1 on Google Mobile without making any adaptations to your site for mobile users at all!