Mobile apps for self-managing chronic health conditions are widely available for download from online app stores. Mobile health (mHealth) apps provide a convenient way of managing health conditions (e.g., congestive heart failure); however, little is known about their design specifications with respect to older adult users. We conducted a 3-phase assessment of human factors issues for common mHealth apps designed for managing congestive heart failure. In Phase 1, we identified two apps often used by older adults. In Phase 2, we evaluated these apps according to standard human factors principles. In Phase 3, we conducted usability testing of the apps with six older adults. We report design issues identified in the apps that limit usability by older adults. We encourage mHealth app designers to improve usability by: 1) providing easier navigation, 2) streamlining data entry processes, 3) providing clear recovery from errors, and 4) simplifying visualizations of data patterns.