Acceptability of the MySmile Mobile Health Application Among Malaysian Adolescents: A Qualitative Study Using the Theoretical Framework of Acceptability

Background Oral health among adolescents remains a public health concern in Malaysia, with persistent challenges in achieving behavioural change through traditional education methods. Given the widespread use of smartphones among adolescents, mobile health (mHealth) applications offer a promising avenue for health promotion. Objective This study aimed to explore the acceptability of the MySmile mobile application (app), designed to improve oral health knowledge and behaviours among secondary school students in Malaysia, using the Theoretical Framework of Acceptability (TFA). Methods This study employed a qualitative approach that involved five focus group discussions (FGDs) with 23 students from two intervention schools that participated in a 12-week MySmile app intervention. Participants were purposively selected based on their gender, school locality, and frequency of app usage. Discussions were guided by a semi-structured topic guide aligned with the seven TFA domains: affective attitude, burden, ethicality, intervention coherence, opportunity cost, perceived effectiveness, and self-efficacy. Data were transcribed verbatim and analysed using the Framework Method. Results The app was perceived as highly acceptable across all TFA domains. Students described it as fun, engaging, and easy to use, with gamified features that enhanced learning. The perceived burden was low, and ethicality was reinforced by the app's culturally appropriate content and privacy features. Participants demonstrated a clear understanding of the app's purpose and reported no significant opportunity cost. Perceived effectiveness was strong, with students reporting improved brushing habits, reduced sugar intake, and sharing of health messages with family. The app also promoted self-efficacy, with students expressing confidence in applying its recommendations independently. Conclusions The MySmile app was well accepted among Malaysian adolescents and appears to be a feasible tool for school-based oral health promotion. These findings support the integration of mHealth strategies in adolescent health programmes and highlight the importance of user-centred, theory-driven intervention design.