“…Theme 1: Acceptability by users [5], [18], [40], [45], [47][48], [55][56][57] Suicide prevention and self-injury apps [6], [35] Text messaging services [6], [24], [36] Social media platforms and mobile phones [54] Chat function Theme 2: Future inclusion of experts-by-experience [3] Adolescents and greater acceptance of technologies [5], [26], [30], [65] Lived experience in design of interventions and trials [32], [46], [50] Importance of user engagement or focus groups [29], [34], [37], [39], [51] Codesign, coproduction, collaboration, user centred Theme 3: Inconsistent use of Public, Patient Involvement (PPI) [66] Consulted mental health experts and not service users [25] Final stages of usability testing [58] Middle stage of research as user-informed [41] Collaborate to support the analysis [18], [43], [53], [55], [57], [59], [61] Members of focus groups or advisory groups [19], [44][45][46]…”