iOS developers are responsible for developing and maintaining applications for mobile devices powered by Apple’s iOS operating system. They use the Objective-C programming language and the Cocoa Touch framework to build interactive applications that can run on iPhone, iPad and iPod touch devices. In addition to developing code, iOS developers also need to be able to troubleshoot issues that may arise during development or after an application has been deployed. They may also be required to work with other teams within the organization, such as design or QA, to ensure that the final product meets all requirements.