Smart mobile devices are becoming increasingly essential daily companions. Applications (apps) are the interface through which the consumer can leverage unique capabilities of smart mobile devices to interact with people, other devices and firms via the supporting mobile ecosystem. Smart mobile devices and apps are influencing how competition is defined and changing how firms do business by improving internal processes and increasing flexibility and convenience for customers. Mobile apps and devices enable users to move from a portable and mobile communication and computing environment to that of a ubiquitous communication and computing environment [u-space]. Discussion in terms of ‘mobile marketing’ is therefore too limiting, our understanding should be ‘ubiquitous marketing’. Six papers explore ubiquitous marketing further. The retail sector provides a contextual setting for paper one and finds that mobile marketing increases value for retailers and consumers. Integration of all retailer / consumer interfaces with mobile marketing to maximise exposure and connectivity between both parties is recommended. Paper two investigates the sources for mobile app ideas in companies and finds that apps developed externally or within the firm with some outside help, were perceived to be more effective. Apps that leverage the mobile devices unique features is central to the methodology proposed for developing an app in paper three. The next three papers examine the impact that mobile apps and devices have on business activities and customer relationships. Paper four finds increased operational efficiency in a Dental  Practice, while paper five identified the opportunity for increased firm-customer interaction in a medical context. Paper six determines that rather than five dimensions of SERVQUAL, financial service quality of apps consists of three dimensions: Reliability, personal and visibles; and that service success can be derived from providing less service. This thesis contributes to a fuller understanding of U-commerce theory. It advances understanding in how apps are making significant changes in how information technology is managed and controlled from an organisational perspective, and how these technology advances can influence consumer interaction. / <p>QC 20160516</p>