Sergio Harashyn - Lead UX & Product Designer, Los Angeles

— award-winning product design leader and mentor

with 20+ years of experience driving innovation through design, collaborating with Cartier, Google, and UCI, and focusing on how people think and innovate.

+45% increase in Daily Active Users (DAU) within 3 months of launch
Average session duration increased by 32% after dashboard redesign
27% boost in account sign-up conversions following an improved registration flow
17% decrease in churn rate due to improved onboarding and in-app guidance
38% increase in successful KYC verifications after UX optimization
30-day retention increased from 42% to 58%

+45% increase in Daily Active Users (DAU) within 3 months of launch
Average session duration increased by 32% after dashboard redesign
27% boost in account sign-up conversions following an improved registration flow
17% decrease in churn rate due to improved onboarding and in-app guidance
38% increase in successful KYC verifications after UX optimization
30-day retention increased from 42% to 58%

+45% increase in Daily Active Users (DAU) within 3 months of launch
Average session duration increased by 32% after dashboard redesign
27% boost in account sign-up conversions following an improved registration flow
17% decrease in churn rate due to improved onboarding and in-app guidance
38% increase in successful KYC verifications after UX optimization
30-day retention increased from 42% to 58%

Data-Driven Results

Case Study: Mymo

View Interactive Prototype

As a UX and Product Designer, I led the design and strategy for a MVP of a Fintech Application. Launching this app enabled the company to sell the product to major clients, driving significant growth in DAU.

An Approach to Financials Digitization

Task completion time reduced by 41% after streamlining workflows
32% fewer clicks required for core actions (e.g., generating invoices, approving budgets)
Reduction in training costs by 35% due to more intuitive navigation and contextual guidance
Data entry errors decreased by 47% after introducing form validation and improved UI feedback
Annual operational savings of $250K+ due to faster task execution and fewer manual processes

Task completion time reduced by 41% after streamlining workflows
32% fewer clicks required for core actions (e.g., generating invoices, approving budgets)
Reduction in training costs by 35% due to more intuitive navigation and contextual guidance
Data entry errors decreased by 47% after introducing form validation and improved UI feedback
Annual operational savings of $250K+ due to faster task execution and fewer manual processes

Task completion time reduced by 41% after streamlining workflows
32% fewer clicks required for core actions (e.g., generating invoices, approving budgets)
Reduction in training costs by 35% due to more intuitive navigation and contextual guidance
Data entry errors decreased by 47% after introducing form validation and improved UI feedback
Annual operational savings of $250K+ due to faster task execution and fewer manual processes

Data-Driven Results

Case Study: Rover ERP

As a Lead Product Designer, I Led the full redesign of a complex ERP system, managing a cross-functional team to improve usability and operational efficiency. Conducted deep UX research through surveys, usability testing, and analytics.

Redesign of a complex ERP system

+28% increase in assisted sales for items not available in-store
83% of users described the experience as “memorable” or “emotionally impactful”
Reduced need for physical inventory by 21% in pilot stores
Zero reported UX friction or crashes during over 500+ AR sessions
52% decrease in customer wait time

Data-Driven Results

Case Study: Cartier

As a Lead Product Designer, I designed an immersive in-store AR experience for Cartier, bridging the physical and digital retail worlds. I collaborated with AI and AR engineers to create a seamless product visualization tool that renders unavailable jewelry items in real time on an iPad.

AR/IoT-powered luxury retail experiences

Task completion time reduced by 35% after UI and flow optimization
25% fewer user errors during in-app car configuration and service scheduling
User satisfaction score (CSAT) improved from 3.9 to 4.7
Reduced rework by 60% through cross-functional prototyping and validation
Piloted in 3 major OEMs with positive feedback from dealer teams

Data-Driven Results

Case Study: Dacia

As a UX Designer, I led the design of a smart car management app, focusing on intuitive user flows and modular UI for customizable in-vehicle experiences. I created a scalable design system, crafted interactive prototypes, and worked closely with product and engineering to align UX with emerging automotive features like BYOD (Bring Your Own Device) and trunk space optimization.

As a UX Designer, I led the design of a smart car management app, focusing on intuitive user flows and modular UI for customizable in-vehicle experiences.

I created a scalable design system, crafted interactive prototypes, and worked closely with product and engineering to align UX with emerging automotive features like BYOD (Bring Your Own Device) and trunk space optimization.

As a UX Designer, I led the design of a smart car management app, focusing on intuitive user flows and modular UI for customizable in-vehicle experiences.

Design for Car Management Application

+42% increase in user onboarding completion after redesigning the sign-up and KYC flow
+31% boost in portfolio engagement, measured by time spent analyzing holdings and using interactive charts
25% reduction in user drop-off during first session thanks to simplified navigation and guided walkthroughs
User satisfaction score (CSAT) rose from 4.1 to 4.8, based on post-session surveys
Support requests related to UI confusion dropped by 47% after implementing the new design system

Data-Driven Results

Case Study: Castle Funds

As a UX Designer, I crafted the user experience for a fintech platform managing active crypto portfolios across spot, futures, and options markets. My focus was on simplifying complex financial data and delivering a seamless, secure, and visually engaging interface for both novice and experienced investors.

As a UX Designer, I crafted the user experience for

a fintech platform managing active crypto portfolios across spot, futures, and options markets. My focus was on simplifying complex financial data and delivering a seamless, secure, and visually engaging interface for both novice and experienced investors.

As a UX Designer, I crafted the user experience for

Designing a Crypto Investment Experience

Task completion time reduced by 41% after streamlining workflows
32% fewer clicks required for core actions (e.g., generating invoices, approving budgets)
Reduction in training costs by 35% due to more intuitive navigation and contextual guidance
Data entry errors decreased by 47% after introducing form validation and improved UI feedback
Annual operational savings of $250K+ due to faster task execution and fewer manual processesAverage

Data-Driven Results

Case Study: Rover ERP

Conducted UX research to optimize interfaces for a complex ERP system, focusing on usability, workflow efficiency, and user needs across diverse roles.

Conducted UX research to optimize interfaces for

a complex ERP system, focusing on usability, workflow efficiency, and user needs across diverse roles.

Conducted UX research to optimize interfaces for

a complex ERP system, focusing on usability, workflow efficiency, and user needs across diverse roles.

UX Research

+34% increase in CTA clicks after hero redesign
+22% boost in form completion rate
Bounce rate reduced by 18%, indicating stronger engagement
+29% increase in scroll depth on mobile within the first fold

Data-Driven Results

Case Study: CRO

Based on competitive analysis and user behavior data, we restructured key elements—price placement, timeline messaging, and call-to-action hierarchy. Personalization, trust signals, and clear visual cues were added to guide users toward the estimate form.

Conversion Rate Optimisation

+46% increase in lead form submissions from hero screen interactions (after A/B testing CTA variants)
+31% uplift in click-through rate (CTR) on video-based hero layouts
Bounce rate decreased by 22%, driven by scroll triggers and value-focused messaging
+18% increase in call-to-sales conversions via embedded phone CTA
Average session time increased by 27%, due to better user flow and interactive content
Micro-conversion actions (chat, scroll, video views) rose by +35%, validating the modular hypothesis strategy

Data-Driven Results

Case Study: SalesX

The layout was built to support A/B testing across multiple micro and macro conversion paths—including AI chat, sales calls, scroll triggers, and contextual CTAs. We introduced video backgrounds, simplified messaging, and modular content blocks to personalize the user journey based on traffic source and intent.

Website Redesign and Optimization

Creative Director

SalesX

2024 – 2025

Lead UX & Product Designer

Zumasys

2023 – 2024

Lead UX & Product Designer

Blue Trail Software

2021 – 2023

Senior UX/UI Designer

Viking Coders

2019 – 2021

Product Designer

IT DEV Group

2016 – 2019

Product Designer

Global Soft Invest

2009 – 2016

Graphic Designer

Freelance

2005 – 2009

Experience

Throughout my career as a designer, I’ve had the privilege of working with some very talented people at great companies.

Download Resume

Empowering Design Teams

Beyond delivering impactful results, I’m dedicated to mentoring teams, fostering collaboration, and cultivating a strong design culture. With expertise in Figma, Adobe Creative Suite, and AI-powered technologies, I turn concepts into elegant, future-proof solutions.

Proud to Be Part of UCI Designathon 2025 as a Judge and Mentor!

What an incredible weekend at UCI Designathon! I had the honor of joining as a judge and mentor, working alongside some of the most talented and driven students I’ve ever seen.

UCI Designathon 2025

My Book: Your Key to a UX Design Career.

What an incredible weekend at UCI Designathon! I had the honor of joining as a judge and mentor, working alongside some of the most talented and driven students I’ve ever seen.

My Book

Get access to the library of over 200 UX resources.

I've gathered valuable materials to aid in your UX education. I prioritize the quality and suitability of resources, having personally vetted most links or received recommendations from trusted sources.

Free UX Resources

What matters most in digital marketing for 2025?

Always start with the trends that matter! Instead of asking how to follow the market, ask yourself how to lead it. Focus on staying ahead by adopting innovation, personalization, and sustainability strategies.

Digital Marketing Trends

In the Beginning was UX.

Thank you to my parents for being good teachers all my life. And they helped me take the first steps toward my dream back in school. So, I found my way into design. It was a long journey through several experiences along the way.