As mobile phone usage continues to proliferate globally, it becomes imperative to consider the anthropometric principles underlying their design and the subsequent effects on users’ posture and psychological behavior. This research investigates the intersection of anthropometric principles and mobile phone design, focusing on user posture and the psychological motivations behind the purchase of high-end devices among Generation Z. Employing a mixed-methods approach, the study combines a comprehensive literature review and surveys to analyze how ergonomic considerations and consumer behavior influence mobile phone usage. Findings indicate that a phone screen size of 5.4 in. offers an optimal balance between usability and ergonomics. The study offers valuable insights into the interplay between anthropometry, ergonomics, and consumer psychology in mobile phone design, ongoing research and adaptive strategies are essential to address the dynamic landscape of mobile technology and its impact on user health and behavior.