Search engine optimization (SEO) was all about web pages -- however, as columnist Janet Driscoll Miller points out, the growth of mobile means that SEOs must now focus on getting apps indexed, too. Google searches now taking place on mobile rather than on desktop, SEOs have been forced to extend their efforts into the mobile space. However, mobile optimization doesn't stop with making websites mobile-friendly; it encompasses mobile apps now as well. The Google Play store reportedly had over 1.4 million apps as of February 2015. With so many apps out there. For example, if a friend emails you about seeing the new movie Tomorrowland, you can invoke Google Now without leaving your app, to quickly see the ratings, watch a trailer, or even buy tickets — then get right back to what you were doing.