Personal climate actions in a popular smartphone app

Smartphone apps hold significant potential to encourage and measure personal climate action at scale. Using global data from the AWorld app, we analysed 139 self-reported actions from 4,369 users (1,088,258 logged actions) to investigate which actions are reported, the temporal patterns, and the relationship with self-reported carbon footprint. The reported action set for a given user is moderately stable over time. Users reported easily repeatable actions most frequently, such as walking or turning off lights, which tend to have modest impacts on greenhouse gas emissions. We found no strong evidence linking the frequency of reported actions to the users' annual self-reported carbon footprints, except in the food domain, or psychological factors such as climate concern. Our study underscores the promise of climate action apps for studying personal climate actions at scale, while also highlighting challenges in evaluating their effectiveness in behavioural change studies. We discuss how these challenges can be overcome.