Jason Yoo. Product designer at WhatsApp.

“I appreciate the time Jason and I got to work together as designers at Crexi. As a teammate, he was a thorough designer that I could always rely on to ask novel questions. When working with Jason, I often left feeling inspired by his innate understanding of people and how they interact with products. This skill, combined with his strong knowledge of UX, enabled him to design experiences that exceeded user expectations and excited our customers.”

“I had the pleasure of working alongside Jason for 3 years on our WhatsApp Calling product. During his tenure, we grew immensely, recently passing a major milestone of over 2 billion calls a day happening over WhatsApp. As one of just 3 designers on the team, Jason played a key role in building the features that drove that growth. From even just the early days of him joining the team, he took on some of the most complex and technically nuanced projects at hand. Over the years, I was consistently impressed with his ability to navigate these difficult projects and bring the rest of the team along, showing us the variety of possible directions we could go in. Jason’s ability to think deeply about tough problems, quickly generate/visualize concepts, and then communicate opportunities to the team make him an extremely valuable member to any team.”

“I've had the pleasure of working with Jason at WhatsApp Calling for 3 years. He is a skilled product designer who consistently delivers intuitive and seamless experiences for billions of users. Jason's focus on simplicity and attention to detail embody WhatsApp's values of craftsmanship, bringing delightful solutions to life.

His ability to distill complex problems into elegant, user-friendly designs is remarkable. Jason's dedication to quality and user-centric design has been a driving force behind many of our projects at WhatsApp Calling in the last couple of years.”

“I am a Senior Software Engineering Manager in WhatsApp, my teams are responsible for developing user-facing features on WhatsApp Calling across Android, iOS, Mac, Windows, and other platforms for billions of WhatsApp users. Over the past 3.5 years, I have had the privilege of working closely with Jason and have been a firsthand witness to his remarkable contributions to our calling product and our team.

Clear & Effective Communication
When working on projects, Jason clearly articulates user pain points, high-level objectives, and multiple solution pathways. His ability to explain the reasoning behind his proposals has greatly benefited cross-functional and engineering teams, fostering a deeper understanding and shared vision for the solutions implemented.

Outstanding Collaboration
Despite being based remotely, we never felt any barrier in our collaboration with Jason. His responsiveness, willingness to incorporate feedback, and respect for diverse perspectives have made him a cherished member of our team.

Growth Guru
Jason has consistently driven many of our growth-oriented projects, effectively removing friction from key user flows. His sharp eye for identifying user pain points, coupled with a balanced approach to driving growth while maintaining product simplicity and intuitiveness, has led to overwhelming results over the years.

Data Awareness
It is rare to see a designer take a rigorous approach to data. Jason consistently evaluates how changes impact user experiences, collaborating closely with both engineering and data teams to quantify effects and validate assumptions. His commitment to a data-informed design process has significantly enhanced our product strategy and execution.

It is an absolute no-brainer for me to work with him again on any product project or company in the future. I wholeheartedly endorse Jason as an invaluable asset to any design team.”

“I had the pleasure of working alongside Jason at WhatsApp for over 3 years, where we collaborated on numerous projects that showcased his excellent design skills and product thinking.

Jason demonstrates a unique combination of creative vision, technical expertise, and strategic insight. He consistently delivered high-quality design solutions with the ability to distill complex problems into intuitive and user-centered designs.

One of Jason’s greatest strengths is his ability to communicate effectively with cross-functional teams. He played a pivotal role in shaping our product roadmap, helping to define key objectives and priorities that propelled our product forward.”

“Having worked directly with Jason for nearly three years at WhatsApp, I can confidently say he’s an exceptional Designer who delivers real impact. He stands out for his remarkable ability to balance user-centric design principles with business objectives. His work on WhatsApp Dialer and Favorites demonstrated this perfectly—he created intuitive experiences that delighted users while driving measurable results for WhatsApp.

What truly sets Jason apart is his collaborative approach. He excels at cross-functional partnership, effectively working across multiple teams while maintaining design cohesion. He’s patient, open to feedback, and never rushes to solutions, instead thoughtfully exploring multiple design options to keep the user front and center. This thoroughness consistently leads to superior outcomes, even in complex organizational environments.

As a communicator, Jason has the rare ability to articulate design rationales clearly to both executive leadership and cross-functional teams. He advocates strongly for simplicity and user needs while remaining flexible enough to adapt to shifting requirements. His direct, structured communication style aligns teams, accelerates progress, and ensures design coherence. He also navigates complex team structures with ease, proactively identifying challenges, iterating quickly, and ensuring execution aligns with broader goals.

Beyond his design skills, Jason’s strategic thinking and proactive problem-solving make him an invaluable team member. I found myself able to trust his judgment completely in our fast-paced environment, knowing he would deliver solutions that seamlessly served both users and business objectives.”

“I've had the pleasure of working with Jason on numerous large-scale projects, delivering incredible success and showcasing his exceptional design skills. He has a remarkable talent for crafting clear, concise designs that are easy to understand, simplifying complex concepts into user-friendly interfaces.

Jason is an excellent team player who collaborates closely with stakeholders and engineering teams, leveraging user research and behavior data to inform his decisions.”

“Few people are a more passionate advocate for users than Jason. I had the pleasure of working with him throughout 2024 on a couple projects for WhatsApp, where he designed the UX for features on both mobile and desktop platforms. His ability to think about all the ways users might interact with a new feature, pose vital questions, and then construct designs for multiple platforms that aren't just functional but beautiful really impressed me. He was very responsive to questions, suggestions and even changes in requirements, enabling us to complete the features on time. Beyond that, he's a cool guy to work with and raises the energy in any room he's in. Any team would be lucky to have him, and I can't wait to see what he designs next!”

“Jason is an exceptional product designer and a true team player. At WhatsApp, he played a key role in shaping some of the most impactful calling features, contributing to a product used by over 3 billion people. Beyond his product work, he was instrumental in brand initiatives and team-building efforts, including designing a celebrated internal magazine for the design summit. Senior, driven, and highly crafted, Jason excels at leading product development from ideation to launch with precision and creativity.”

“Jason thinks deeply about design (and the world!). The world's greatest designers are unwavering interrogators, knowing that the world is never static—that their brilliance comes from insights few others have. Jason is one hell of an interrogator. At Crexi, he honed and flexed his superpower, creating beautifully effective modern mobile designs that helped our app stand out and rise above all other real estate apps.

I learned so much from Jason. Working with him has profoundly influenced my own approach to product design and development. His blend of creativity, analytical thinking, and attention to detail has set a new standard for me.”