Brick and mortar. Click and mortar. Many businesses have opportunities to expand their sales or enter new markets by extending their services or products through mobile applications. The Little Blue Book is one case in point. Published in 147 separate metropolitan areas, The Little Blue Book has long been a premier tool that physicians use to find and refer patients to other physicians. A copy can be found in most doctors\u2019 offices in the markets they serve. And now copies can be found on doctors\u2019 iPhones and Blackberrys. A prescription for highly cost-effective, rapid expansion.