Objective: The purpose of this study was to examine the feasibility and effectiveness of a suicide prevention smartphone application. Method: Thirty-six non-Aboriginal Australians aged between 16 and 42 years (67% female) were recruited from a tertiary mental health service where they were receiving treatment for suicide risk. Participants were asked to use the BeyondNow safety planning smartphone application to manage their suicide safety plan during a 2-month trial, as an adjunct to treatment as usual. A survey battery designed to measure feasibility and effectiveness of the smartphone app plus treatment as usual intervention was completed at baseline and follow-up. Results: A vast majority of participants used the app to view and edit their safety plans and reported that the app was easy to use. A reduction was observed in participant severity and intensity of suicide ideation, and suicide-related coping increased significantly. No significant changes were observed in suicide resilience. Conclusions: The BeyondNow safety planning smartphone application was shown to be feasible and effective as an adjunct to mental health treatment among patients at risk of suicide.