There are many great templates and design examples out there. Due to the fact that different people like different things and companies do have their own corporate style guides use this one as a template to customize it. Feel free to download it on Tableau public and modify it so that it fits to your corporate design and the needs you’re having.

Another great template for mobile optimized dashboards can be found from one of our Tableau Zen Masters: Kelly Martin

http://www.tableau.com/about/blog/2015/8/tips-building-dashboards-smartphone-43225