Difficulty controlling anger is the most commonly reported reintegration concern among combat Veterans, especially those with a diagnosis of posttraumatic stress disorder (PTSD). Problematic anger is associated with significant functional impairment. In the current project, the investigators will compare the Mobile Anger Reduction Intervention (MARI) with a health education mobile intervention (HED) among Veterans with PTSD and problematic anger. Participants will be randomized to the MARI or HED condition. The hypothesis is that participants in the MARI condition will experience greater anger reductions and functional improvements relative to the HED condition.