Through features available on smartphones (e.g., camera/video/voice recording; simple message service; internet-access; global positioning system), there are novel methods to interface with and support clients outside of defined treatment sessions. Through the use of these features, mHealth applications can be used to engage, educate, connect, track, and remind clients. These applications can use push (send communications) or pull (client's access tools on their own) mechanisms to engage the client in behavioral change activity. mHealth applications that integrate push and pull methods offer a significant opportunity to enhance outcomes across a range of health and behavioral health challenges and populations.