Background: Digital learning tools have proliferated among healthcare workers in India. Evidence of their effectiveness is however minimal. We sought to examine the impact of the Safe Delivery App (SDA) on knowledge and confidence among frontline health workers (HW) in India. We also studied whether facilitation to address technical challenges enhanced self-learning. Methods: Staff nurses and nurse-midwives from 30 facilities in two states were divided into control and intervention groups through randomization. Knowledge and confidence were assessed at baseline and after 6 months. Three rounds of facilitation addressing technical challenges in downloading and usage along with reminders about the next phase of learning were conducted in the intervention group. A user satisfaction scale along with qualitative interviews was conducted in the intervention group at the endline along with qualitative interviews on facilitation. Results: The knowledge and confidence of the healthcare workers significantly increased from the baseline to endline by 4 percentage points (P < 0.001). The participants who received facilitation had a higher mean score difference in knowledge and confidence compared to those who did not receive facilitation (P < 0.001). The participants were highly satisfied with the app and video was the most-watched feature. They reported a positive experience of the facilitation process. Conclusion: The effectiveness and acceptability of the SDA indicate the applicability of mHealth learning tools at the primary healthcare level. In a time of rapid digitalization of training, facilitation or supportive supervision needs further focus while on-ground digital training could be invested in to overcome digital illiteracy among healthcare workers.