Let's talk about UI Design first, I can offer you the designing skills which can help us to create beautiful UI designs. The design tools which I use are: Sketch and Adobe XD. Here is link where you can check few designs and make your decision. I have used either of these tools for them.
https://www.behance.net/techieviking
Let's talk about UI development, I can offer you the development skills which can help to develop UI designs. In other words, we gonna bring our UI design to life. For development, I use HTML5, CSS3, Bootstrap, Angular, CSS Preprocessors like SASS and LESS, Javascript, Typescript. I can help you to create everything you need to build for the front end. :)