Will the smartphone become a useful tool to promote physical activity?

Affiliations

• ¹ Department of Medicine, Division of Cardiology, University of California, San Francisco, San Francisco, CA 94143, USA; Bakar Institute for Computational Health Sciences, University of California, San Francisco, San Francisco, CA 94143, USA.
• ² Department of Medicine, Division of Cardiology, University of California, San Francisco, San Francisco, CA 94143, USA. Electronic address: greg.marcus@ucsf.edu.