adding chat functionality on a pre built ios app

I'm looking for an experienced iOS developer to help me add chat functionality to a pre-built iOS-Swift app I'm working on. It is an online quizzing app where chat between students and instructors is required. As this is a time sensitive project, I need someone who can work quickly and efficiently. If you think you are the right person for this job, please reach out. I'm looking forward to hearing from you soon and thank you for your time!