Many public health agencies, including the U.S. Department of Veterans Affairs (VA), have identified the use of mobile technologies as an essential part of a larger strategy to address major public health challenges. The VA's National Center for PTSD (NCPTSD), in collaboration with VA's Office of Mental Health and Suicide Prevention and the Defense Health Agency inside the U.S. Department of Defense (DoD), has been involved in the development, evaluation, and testing of 15 mobile apps designed specifically to address the needs and concerns of veterans and others experiencing symptoms of posttraumatic stress disorder (PTSD). These applications include seven treatment-companion apps (designed to be used with a provider, in conjunction with an evidence-based therapy) and eight self-management apps (designed to be used independently or as an adjunct or extender of traditional care). There is growing evidence for the efficacy of several of these apps for reducing PTSD and other symptoms, and studies of providers demonstrate that the apps are engaging, easy-to-use, and provide a relative advantage to traditional care without apps. While publicly available apps do not collect or share personal data, VA has created research-enabled versions of many of its mental health apps to enable ongoing product enhancement and continuous measurement of the value of these tools to veterans and frontline providers. VA and DoD are also collaborating on provider-based implementation networks to enable clinicians to optimize implementation of mobile technologies in care. Although there are many challenges to developing and integrating mHealth into care, including cost, privacy, and the need for additional research, mobile mental health technologies are likely here to stay and have the potential to reach large numbers of those with unmet mental health needs, including PTSD-related concerns.