Hiring a Cocoa Touch developer is beneficial for designing high-quality iOS applications. They have expertise in Cocoa Touch, the UI framework for creating fast, responsive, and visually appealing iOS applications. They understand how to optimally use its features, including multi-touch gestures, animation, and navigation. Their knowledge of Apple's ecosystem ensures seamless integration with iOS features and services. With their skills, they can create applications that provide an exceptional user experience, thus increasing user engagement and satisfaction. Their knowledge can also help in troubleshooting and solving any potential issues swiftly.