(BrandWeek) — When it comes to mobile, the ad industry has seemed stuck in its own version of Waiting for Godot. Each year for the past decade, the industry has hyped mobile’s great potential, only to face myriad technical and business obstacles. Now, thanks to advancements by Apple and innovations by Google, mobile has arrived as a truly effective platform for brands. So far, however, few marketers have built a lasting presence, settling instead for flash-in-the-pan approaches that result in gimmicky apps. But a smaller number of forward-thinking brands are using mobile platforms to solve real problems for their customers and differentiate their products and services. Here are three companies doing mobile right.