Responsive web design, a concept that allows for an optimized website viewing experience across multiple devices, is no longer the wave of the future. Instead, responsive design is here to stay. Trends within the world of responsive design might change from year to year, but as long as the market demands a wide variety of devices the concept of building one website that is functional and aesthetically pleasing on screens and devices of all sizes will be the prevailing philosophy for years to come. So what are the latest responsive design strategies for 2015?