If you are a web designer then you might spend a lot of time thinking about the look and feel of the website. You would try to design a site that feels intuitive and is easy to use while providing a great user experience. These types of roles are usually categorized as user experience designers, but you will most likely see the roles advertised as UX developer/designer. Depending on who you are designing the site for, you will meet with business partners, customers, and users to get a better understanding of what hey are looking for, which we call requirements. You will then try to meet these requirements while adhering to some standards, usually interface design standards like Google's material design.
These UX designers will then build mock ups and provide them to the UI developers who then code out the site according to the specifications. A UI developer is much more focused on meeting the requirements by building out the mocks using some frameworks.
So to summarize, typically, your daily life consists of gathering requirements, building mock ups, meeting with business partners and customers to design a universally usable site that meets the requirements given to you that you feel your UI developers can put together. This goes the same for Web designers and Mobile app designers. Your mock ups and design standards will change depending on the platform(web vs mobile).
I am a Full Stack Software Engineer and I interface with UX designers to try to figure out the best approach to creating beautiful, usable and efficient user interfaces that meet industry standards while trying our best to give our users the best experience possible.
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