Principles and theories of behavioral decision-making (BDM) are applicable to any field, but they have special import for health care, where low-impact but repeated decisions can significantly affect quality of life. Unfortunately, limited research has focused on effective behavioral design for personal health management mobile apps. This paper addresses patient engagement approaches using the National e-Health Collaborative's "Patient Engagement Framework" and outlines specific implementations of behavioral decision theory to create an effective system for self-care.