The internet is evolving, and mobile is quickly becoming the simplest, most convenient way to access online information.
More accessibility is the case for both the advertiser and the mobile user. Since mobile users can now access the internet from almost anywhere, the internet has become a lot more accessible. That means it's important for your business to stay accessible by providing a website for your mobile visitors. Mobile web development has more features than a typical PC website. With options like "click-to-call", mobile users can call you with a push of a button. Mapping applications and GPS location services mean a mobile user can simply click from your mobile website and automatically be shown your nearest locations, on a map.
Not only is the mobile community more accessible, they're more localized. Through methods like triangulation and built-in GPS, mobile users can be tracked to their exact location, meaning you get ads to the right audience. Personalized local websites have the ability to display your ad only in the regions you want.
So maybe the question shouldn't be "Why mobile?", but rather, "Why not mobile?"