Objective: Borderline personality disorder (BPD) is a severe mental disorder characterized by emotional crises. To date, crisis interventions for BPD have been conducted via telephone calls and emergency units, which are associated with an extra amount of resources. The aim of this research was to test the usability and satisfaction with a psychotherapeutic mobile app for self-managing crises in BPD. Method: The B·RIGHT app was designed based on Artificial Intelligence psychotherapeutic algorithms. Usability and satisfaction with the app were assessed in 25 outpatients diagnosed with BPD (84% female, mean age = 35.80 years) using the System Usability Scale (SUS) and other questionnaires. Clinical features were assessed using the Borderline Symptom List, the Difficulties in Emotion Regulation Scale and Beck’s Depression Inventory. Results: Patients with BPD considered the app user-friendly (mean total score = 4.03) and highly satisfactory (mean total score = 4.02), resulting in a positive user experience (mean total score = 4.09). Total usability was negatively associated with age (r = −.44), positively associated with educational level (rho =.47) and with overall emotion dysregulation (r =.51), and negatively associated with depression severity (r = −.47). Conclusions: The usability and satisfaction testing of the B·RIGHT app showed promising findings, which warrant further research in order to validate its effectiveness.