ui designer for app and web

I am looking for an experienced UI designer to help create the interface for my app and web project. The focus of my project is for the UI designer to create a professional look for the interface that appeals to my target audience and is cohesive between the app and website. The app and website will both be used for portfolio purposes and require the UI designs on 6-10 screens/pages. As such, the UI designer must possess a keen eye for design and ability to create a user-friendly interface across both platforms. The UI designer should also be able to bring modern designs and think outside the box with their ideas. A strong portfolio of previous work is necessary for consideration.