Smartphone applications are recognized as key tools in modern technology. Enhancing the design language of these apps improves the interactive communication experience for tourists. Tourism apps typically offer features like displaying environmental map infographics, highlighting important identity elements of a location, presenting routes, and providing details about transportation systems, tourist attractions, and points of interest. From a professional standpoint, the design of smartphone applications is always grounded in a structured system called design language. It is evident that in current design practices, the functional aspects of user interface (UI) and user experience (UX) are often not clearly defined and are frequently implemented without employing contemporary design styles. The primary focus of this research is to develop an understanding of the application design process based on design style and structured design, exploring how UI design, when guided by UX principles, can address design challenges and foster positive interaction between users and the app. This study analyzes the UI and UX of two tourism applications by examining the role of design language in leading technology companies such as Google, Apple, and Microsoft. The findings suggest that a deliberate and well-organized design process within an application can shape its identity and success, while also facilitating effective interactive communication with users.