Many consumers nowadays wish to reduce their smartphone usage in the hope of improving productivity and well-being. We conducted a pre-registered field experiment (N = 112) over a period of several weeks to test the effectiveness of two widely available digital strategies for screen time reduction. The effectiveness of a design friction intervention (i.e., activating grayscale mode) was compared with a goal-setting intervention (i.e., self-commitment to time limits) and a control condition (i.e., self-monitoring). The design friction intervention led to an immediate, significant reduction of objectively measured screen time compared with the control condition. Conversely, the goal-setting intervention led to a smaller and more gradual screen time reduction. In contrast to the popular belief that reducing screen time has broad benefits, we found no immediate causal effect of reducing usage on subjective well-being and academic performance.
Keywords: design friction; digital nudge; goal-setting; screen time; smartphone; time limits.