UI designer

My project is in need of a UI designer to create a mobile app for my college where one can ask general Q&A about the campus(like quora). I'm not sure what specific design I'm looking for, but I need something with intermediate functionality. I'm looking for someone who can turn my ideas into a modern and attractive design that fits in with the current trends of mobile app interfaces. I need a reliable designer who is flexible enough to incorporate changes and updates to the design as required.