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USA, Austin

Yevhen Piotrovskyi
CTO, Co-Founder
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Back to all articles
09 April 2021
7 min to read

Top UI Developers Interview Questions To Ask

Vitalina Lytvyn
Design consultant

The UI designer plays an important role in website building as the user interface allows users to go inside the site and creates an initial impression.

The UI developer is a complex and multi-tasking job. Guided creativity, logic, and analytics – this is how one can describe the work of a UI developer. It’s highly important to find a qualified specialist. The success of your product as a whole may depend on this.

Given the fact that a lot of people don't really understand the exact difference between UX and UI, it's no surprise that companies often hire one specialist for both shoes. This article will help you see what the user interface developer's role actually is and help you find a perfect UI developer in your team. Here we’ve prepared the most essential interview questions to ask UI developers candidates – check them out!

1. What are the responsibilities of a UI developer?

To answer this question one can clarify what the user interface actually is. UI is a specific rendering process that allows you to implement a prototype of a site, application, or other web resources. First of all, the UI includes active work on the graphical component of the interface: animations, illustrations, buttons, and other elements of the site are created, including fonts, colors, shapes.

Initially, the user experience is determined and the target audience is researched. Depending on the needs of visitors, the color palette, shapes, and the structure of the placement of the objects is specified. The user interface must be clear, and one of the main tasks of a UI designer is to define whether the site is visually user-friendly, whether it is easy to hit the buttons, and whether the text is readable. In simple words, the UI designer makes sure that the user's interaction with the site is harmonious and efficient. User interface design is based on creating a clear visual, so that the visitor immediately understands how to use the product.

2. Can you describe your typical design process?

It’s quite a comprehensive question. And a candidate’s answer can help to assess their ability to integrate into your team of web developers. The design process may differ from person to person, and it’s helpful for you to know if the candidate’s processes are similar to your company’s ones in a meaningful way. You can expect a candidate to tell you what makes their design process unique, but also show that they are also able and willing to follow standard processes.

3. If the website is slow, how would you diagnose and fix the issue?

This is another question allowing you to assess the candidate process and to consider their error handling experience. You can expect the candidate to explain to you what can slow down your site and what can be done to speed it up.

4. In which way do you cooperate with the UX developers?

Your potential UI developer should be comfortable discussing this question since both UX and UI developers work directly with design, which means they need to be on the same wave.

When a UI developer needs to change something that a UX specialist has provided, they should jointly discuss wireframes, UI elements, personas, and think about how the changes they make could influence the user journey as a whole. UI and UX developers should also jointly test the product at the development stage and provide feedback.

5. Can you explain what the aesthetic-usability effect is?

This is a feature of our perception: a more attractive design is always perceived as more convenient, even if it’s actually not. The skilled specialist should bear in mind that this effect can affect the user more than one may think. This, in turn, determines the behavior of the users and their idea of the ease of use of the system.

6. How to make sure your web design is user-friendly? What steps would you take?

Here a potential UI designer is expected to talk about collaboration with UI designers on a conceptual web page concept that promotes user-centered interaction and testing the site with users to achieve optimal design. Candidates also have to make sure that the web page is optimized for viewing on a smartphone.

7. What is Call To Action? Is it important for the UI developer?

A call to action is one of the crucial elements of a website, platform, or app. Simply put, this is an interface element that pushes the user to the desired action: purchasing, downloading, donating money, etc. The UX designer's wireframe and prototype should reflect which call-to-action would ideally captivate the user. A highly skilled UI developer should immediately single out the indicated CTA and pay more attention to this element when designing. An element can be accentuated by color, size, font, position, and alignment – and is the task of the UI designer.

8. What is a responsive web design?

This is a page design that provides a correct and convenient site display for a mobile user. A responsive website automatically adjusts itself to the size of the browser window. This means that there is no need to customize the site for a particular type of gadget, the responsive web resource is displayed correctly on smartphones, tablets, laptops, etc.

9. Explain what web accessibility is. Why is it important?

Web accessibility implies the design and development of websites and apps, taking into account the possibility of their use by people with disabilities (hearing impairment, vision, cognitive impairment, neurological disorders, disorders of physical development, etc.). An accessible web design increases usability and the degree of user satisfaction. Web accessibility can help strengthen a brand, drive innovation, and increase the company's presence in the marketplace.

10. How can you test website performance?

The Chrome Lighthouse test may be used for testing site performance. The website performance is great if the load time is under 5 seconds; is good if the load time is between 5 and 8 seconds, and is considered bad if the load time is more than 8 seconds.

11. Do you keep up with design trends in the industry? Which ones do you like and which ones do you prefer to stay away from? Why?

Simply put, this question allows you to evaluate the candidate's understanding of design trends in the industry. This is a great chance for a candidate to showcase their design values and logic to their design practices – whether they're chasing trends or opting for accessibility and inclusiveness where appropriate.

12. Can you give an example of a website or application with an unsuccessful user interface?

This question contains an element of reverse psychology. You can, of course, just ask for a description of a good user interface. But the point of this question is to avoid the too obvious and too generalized answer.

By describing elements of an unsuccessful user interface, a developer demonstrates their design values for things like buttons, input fields, login screens, shapes, sizes, positions, colors, etc. A highly qualified candidate should always be able to explain in detail why a particular user interface may not please the end-user.

Now you know what to ask a user interface developer during the interview and can be sure that you’ll choose a highly skilled specialist for your company.

Also, if you’re looking for a professional team of UI designers, you can get in touch with Yojji experts. They have a great sense for UI. Our developers follow the latest UI trends when creating our products and will be happy to create a customized software product for your business in line with best industry practices. Dozens of successfully completed projects, thorough quality control, and flexible models of cooperation – that’s what you’ll get if you choose Yojji.

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NL, Amsterdam

Ildar Kulmuhametov
CEO, Co-Founder

USA, Austin

Yevhen Piotrovskyi
CTO, Co-Founder