Sample size. A a total number of 50 participants per study (i.e., 50 participants without depressive symptomatology, and 50 participants with mild depressive symptomatology) was estimated based on previous studies testing mobile phone applications for depression that reported large within group effect sizes. The calculation of the sample size was conducted with G*Power 3.1. for ANOVA (Repeated measures, between factors), assuming an alpha level of 0.05, a statistical power of 0.80, and a large effect size (Cohen's f = 0.355).