Introduction <p>Temporal bone dissection is a foundational component of otolaryngology surgical training, traditionally performed under operating microscopes that are costly and unavailable in many resource-constrained institutions. We describe and evaluate a novel, low-cost smartphone-based Camera-Based Mastoidectomy Training (CBMT) unit as an adjunct to the operating microscope for temporal bone dissection training.</p> Materials and methods <p>A pilot randomized crossover study was conducted at a tertiary care centre. Fourteen otolaryngology residents with no prior independent cadaveric temporal bone dissection experience participated in a one-day structured workshop. Participants were randomly assigned to one of two equal groups. Each group performed standardized temporal bone dissections using both an operating microscope and the CBMT unit in a crossover fashion on separate fresh cadaveric specimens. Usability was assessed using a 10-item questionnaire on a 5-point Likert scale, analysed using the Wilcoxon signed-rank test.</p> Results <p>The CBMT unit scored significantly higher (<i>p</i> &lt; 0.05) than the operating microscope for comfort (<i>r</i> = 0.57), ease of unit adjustment (<i>r</i> = 0.71), three-dimensional clarity (<i>r</i> = 0.71), magnification adjustment (<i>r</i> = 0.77), illumination adjustment (<i>r</i> = 0.86), ease of mentoring (<i>r</i> = 0.66), and mobility (<i>r</i> = 0.86). No significant differences were observed for confidence, hand-eye coordination, or ocular strain.</p> Conclusion <p>In this pilot study, the CBMT unit demonstrated favourable usability, ergonomic characteristics, and teaching facilitation compared to conventional operating microscopes. These preliminary findings suggest that the CBMT unit may be a feasible and acceptable low-cost adjunct for temporal bone dissection training, particularly in resource-limited settings. Larger multicentre studies incorporating objective performance metrics are required before broader adoption.</p>