Library patrons are adopting mobile devices for personal and other uses. The ubiquity of mobile devices will lead to changes in how and where learning and education happens. Libraries have wanted to become ubiquitous by making resources and services available anywhere, anytime. Reference librarians can use mobile devices and applications to include services in mobile learning environments. Challenges to libraries include uncertainty about which technologies to adopt in a rapidly changing technology landscape, the cost of technology adoption, staffing for 24–7 facilities, diversity of needs and preferences among library patrons, and the need to offer stable, consistent services. The combination of mobile librarians, mobile patrons, and mobile...