This document summarizes key issues in mobile health (mHealth) based on interviews and research. It identifies five main categories of issues: policy and regulatory concerns around privacy and FDA regulation; wireless environment challenges of multiple networks and costs; health system issues like reimbursement, integration, and business models; challenges implementing mHealth like immature understanding and lack of evidence; and gaps in mHealth research around effectiveness, pace of technology, and underserved populations. Opportunities discussed include leveraging health reform, federal guidance, collaboration, and improving practice and research through iteration.