Background: Neurological and psychiatric conditions represent significant public health challenges, with traditional treatments such as psychotherapy and pharmacotherapy often limited by adherence issues, side effects, and variable efficacy. Deep Brain Sound Stimulation (DBSS) is a novel, non-invasive neuromodulation technique that utilizes calibrated auditory frequencies to enhance neural synchronization and plasticity through frequency-following responses (FFRs). This approach offers a targeted and scalable alternative to conventional methods like Transcranial Magnetic Stimulation (TMS) and Transcranial Direct Current Stimulation (tDCS). Objective: This large-scale observational study aimed to evaluate the safety, user satisfaction, and perceived therapeutic benefits of DBSS across various neurological and psychiatric conditions, including depression, anxiety, Attention-Deficit/Hyperactivity Disorder (ADHD), Post-Traumatic Stress Disorder (PTSD), and hypertension. Methods: Data were collected from 6,437 Apple App Store users who completed at least one full-treatment DBSS protocol via the Vital Tones mobile application. Additionally, 380 users participated in voluntary in-app surveys providing detailed feedback. User satisfaction was assessed through descriptive statistics of survey responses and app engagement metrics, including refund rates. Results: Among full-treatment users, 98.52% reported overall satisfaction, accompanied by a low refund rate of 1.48%. Users reported improvements in cognitive focus, emotional regulation, and motor coordination, particularly in managing anxiety, depression, ADHD, PTSD, and hypertension. Mild side effects, such as dizziness and headaches, were infrequent and transient. With over 3 million sessions administered globally since 2014, DBSS demonstrates high feasibility and potential benefits in a home-based, non-invasive setting. Conclusions: DBSS appears to be an effective and accessible non-invasive neuromodulation tool, characterized by high user satisfaction and minimal adverse events. These preliminary findings support DBSS’s potential as an alternative or complement to traditional neuromodulation treatments. However, further validation through randomized controlled trials (RCTs) and objective neurophysiological assessments is necessary to confirm its efficacy and optimize its protocols.