The Lift2 study is a 2x2x2 factorial experimental trial among survivors of critical illness with elevated post-discharge symptoms of depression. The study was run at 3 sites (Duke, Colorado, and Oregon) from August 2019 through July 2023. The Lift intervention is a mobile app-delivered mindfulness intervention. A total of 247 participants were randomized to 1 of 8 different groups as determined by 3 two-level intervention component combinations: intervention introduction method (mobile app vs. therapist call), mindfulness meditation dose (once daily vs. twice daily), and management of increasing symptoms (mobile app vs. therapist call). Participants were followed up at 1 and 3 months post-randomization. 77% and 74% of participants were reached at 1 and 3 months, respectively. The primary outcome was Patient Health Questionnaire 9-item (PHQ-9) at 1 month. Results show a significantly large main effect of mindfulness meditation dose on the primary outcome. Additional main effects and interactions were examined on both the primary outcome at 3 months, and all secondary outcomes at 1 and 3 months. The results supported a final optimized version of the intervention including mobile app introduction, twice daily mindfulness meditation, and app management of increasing symptoms. Further details can be found in the forthcoming main results paper.