<![CDATA[Learning biology, particularly cells and metabolism, requires students to understand structures, sequences, and dynamic processes that are difficult to observe directly. This study aimed to analyze students’ and teachers’ needs as a basis for developing mobile-based biology microlearning for senior high school students. A descriptive needs analysis involved 31 Grade 11 students in the Mathematics and Natural Sciences track and three biology teachers at SMA Negeri 23 Makassar. Closed-ended data were analyzed using frequencies, percentages, means, and standard deviations, while open-ended responses were coded descriptively. Smartphones were the primary student devices (77.4%), and videos of 3–5 minutes were the most preferred duration (51.6%). All students needed offline access, 93.5% needed subtitles, and 90.3% agreed that short, stepwise materials could support their focus. The most frequently identified difficult topics were enzyme and coenzyme inhibition (32.3%), light-dependent reactions of photosynthesis (29.0%), and the fluid mosaic model of cell membranes (22.6%). Teachers emphasized dynamic media, curriculum-aligned materials, editable resources, formative question banks, data-efficient materials, and technical support, while only one teacher reported confidence in creating simple digital materials. The findings indicate that the initial design should provide 3–5-minute single-concept segments, 360p–480p video options, offline access, subtitles and transcripts, stepwise visualizations, and short quizzes with explanatory feedback. The study provides context-sensitive initial specifications for mobile-based biology microlearning, which should be followed by content validation, prototype development, usability testing, and effectiveness evaluation.]]>
