Front-End Developer for App Integration

We need a developer to build the front end of our app and connect it to the existing backend. The work includes creating responsive user interfaces, implementing core app features, and reviewing backend integration to ensure smooth functionality. You should be comfortable working on both front-end and backend tasks, troubleshooting issues, and helping improve the overall user experience. This is a part-time project with potential for future collaboration. We need someone with strong experience that can work quickly as we are on a tight deadline.