This chapter addresses the critical link between Explainable Artificial Intelligence (XAI) and Trust in smart applications. As AI systems grow across multiple industries, including healthcare, banking, and transportation, the need for transparency and accountability becomes clearer. The chapter starts by describing essential topics such as smart applications, AI, and XAI, followed by a study of the emergence of XAI and its relevance in encouraging user confidence. It underlines the issues created by “black-box” models, which limit comprehension and lead to distrust among users. The chapter highlights the significance of giving explicit, interpretable explanations for AI-driven judgments through a review of several XAI strategies and their consequences for trust. Ultimately, it highlights that boosting explainability is vital for assuring AI technology’s responsible and ethical deployment, driving increased acceptance and reliance on smart applications.