The rapid growth of fast fashion has caused serious environmental harm and encouraged unsustainable consumption habits. At the same time, many people accumulate excess clothing, while vulnerable populations struggle to meet basic apparel needs. To address this gap, this project introduces EcoChic, a mobile application that promotes sustainable fashion practices and facilitates clothing donations. Its main features include a digital closet, StyleMate AI, and an interactive donations page. The digital closet enables users to organize clothing while receiving personalized sustainability scores and care recommendations via a ChatGPT API call. StyleMate AI offers eco-friendly outfit suggestions and shopping guidance, with an experiment showing that 50% of responses perfectly matched expected outputs and the remainder were rated strong to moderate. The donations page uses a map interface to locate nearby donation centers, making it easier for users to redirect unwanted clothing. By combining personalized sustainability insights with practical donation tools, EcoChic encourages mindful consumption, reduces textile waste, and supports both sustainable consumer behavior and community needs.