Scientific Calculator - The calculator should have an intuitive interface with clear button design and convenient arrangement of functions. It can be designed with button highlighting upon hover or click to enhance user interaction. Additionally, the option to resize the calculator window can be added so that users can customize it to their preferences. Multiple theme options can be offered, such as light and dark, allowing users to choose the most suitable one. It should also have the capability to save calculation history, enabling users to easily revisit previous operations and results.