There are ongoing questions regarding the similarities and differences in the clinical impact and processes of change for cognitive restructuring and cognitive defusion. This clinical component test compared 87 adults high in self-criticism randomized to a cognitive defusion mobile app, restructuring app, or waitlist condition for two weeks. Equivalent improvements were found from the defusion and restructuring apps relative to the waitlist in self-criticism and distress as well as decentering, self-compassion, and dysfunctional attitudes. However, the defusion condition had a more consistent pattern of improvements relative to waitlist. Improvements in cognitive decentering, self-compassion, and dysfunctional attitudes mediated effects for cognitive defusion relative to waitlist. These mediators were inconsistent for cognitive restructuring. Improvements in self-compassion and cognitive decentering correlated with improvements in outcomes in the defusion condition, but not the restructuring condition. Overall, these results suggest mobile apps providing cognitive defusion and cognitive restructuring strategies are equally effective, but work through distinct processes of change.