Hiring a Google App Engine developer provides several benefits. They are skilled in building, deploying, and scaling web applications and services on the same infrastructure as Google. They can effectively manage apps, databases, and traffic without worrying about the underlying infrastructure. Their expertise in Google's technology stack ensures seamless integration with other Google services. They can help you leverage Google's powerful cloud computing capabilities to develop robust, scalable, and efficient applications. Their knowledge of platform-specific best practices can also enhance the performance and security of your applications.