Sebastian Petrina, Designer in Bucharest, Romania
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Sebastian Petrina

Verified Expert  in Design

Bio

Sebastian is a senior product designer with 15+ years of experience shaping intuitive, high-performing digital products. He has worked with world-class design teams at top enterprises and helped startups refine their vision, secure funding, and scale successfully—both as a collaborator and co-founder. With expertise in UI/UX, design systems, AI, and data visualization, he creates seamless, scalable solutions that drive engagement, optimize workflows, and deliver measurable business impact.

Portfolio

Work Experience

Lead Product Designer

2022 - 2024
ESX
  • Redesigned the ESX mobile app and website, driving a significant increase in monthly revenue post-launch by optimizing subscription and engagement flows.
  • Designed Romania’s first fitness expert marketplace, onboarding 500+ trainers in the first month, expanding ESX’s service ecosystem.
  • Built and scaled design systems for mobile and web, ensuring code-ready, responsive components that streamlined development and improved UX consistency.
  • Led cross-functional teams through ideation, prototyping, and testing, launching five new high-impact product features.
  • Redesigned core user flows using the design system, enhancing conversion rates, usability, and visual consistency.
  • Introduced Agile design sprints tailored for ESX, organizing 5-day sprints that resulted in a more streamlined and effective design process.
  • Conducted user interviews and usability tests, uncovering critical UX issues, optimizing acquisition funnels, and training the team in research methodologies.
  • Conducted market and competitive research, identifying top opportunities to improve profitability and acquisition attractiveness.
  • Developed a landing page builder, reducing marketing, design, and development efforts, accelerating campaign launches, and boosting lead generation.
Technologies: Figma, Miro, Jira, Maze, Slack, Google Workspace, FigJam, Adobe Creative Suite, Design Thinking, Google Design Sprints, Design Systems, SaaS, Agile, Design Leadership, Visual Design Language, User Acceptance Testing (UAT), Usability Testing, User Research, MVP Design, Digital Product Design, Fintech, Healthtech

Product Designer

2022 - 2022
The ORCA Network, Inc.
  • Designed a responsive web app that centralized funding opportunities, collaboration, and startup resources, making entrepreneurship more accessible.
  • Developed an intuitive UI/UX that streamlined investor-founder interactions, contributing to 2,225+ meetings facilitated through the platform.
  • Led user research and testing, engaging with startup founders and investors to refine workflows, improve engagement, and enhance matchmaking efficiency.
  • Built an interactive dashboard, providing startups with clear insights into funding opportunities and accelerators, helping 2,100+ startups navigate their growth journey.
  • Collaborated with developers to build a scalable design system, ensuring UI consistency across web and mobile, reducing front-end development overhead.
  • Designed a gamified waitlist, allowing users to vote on challenges, create problem “pods,” and track their score and ranking. Implemented an interactive referral system that encouraged engagement, helping grow the community before launch.
Technologies: User Interface (UI), User Experience (UX), Web Design, B2C, Responsive Web Design (RWD), Mobile Design, Digital Product Design, Figma, Miro, Maze, Adobe, Notion, Slack, Web App UX, Web App UI, Dashboards, Dashboard Design, Web Dashboards, Responsive UI

Product Designer

2021 - 2022
Babylon
  • Elevated the visual design of Babylon’s products, creating a unified visual design language that improved usability, brand consistency, and scalability.
  • Designed components, patterns, and layouts for a global design system, ensuring clean, accessible, and cohesive user experiences across all Babylon products.
  • Redesigned and updated app screens using the newly established design system, improving visual hierarchy, accessibility, and user experience across mobile and web.
  • Conducted a comprehensive competitor analysis on data visualization, evaluating industry leaders like Apple Health, Fitbit, and Samsung Health to define best-in-class solutions.
  • Designed advanced data visualizations, including bar, line, and range charts, metrics cards, and summary pages, ensuring clarity, accessibility, and actionable insights for users.
  • Strategized improvements for homepage engagement, designing a dynamic content framework that allows internal teams to surface personalized, relevant health insights.
  • Redesigned the UX of Babylon’s internal DNA Sandbox app, enhancing information architecture, navigation, and content structure to improve usability and adoption.
  • Led UX research and conceptual design for a goal-based lifestyle behavior improvement tool, defining user flows, engagement strategies, and data-driven health recommendations.
Technologies: Figma, Miro, Design Systems, Design Language, UX Design, UI Design, Data Visualization, Mobile App Design, Digital Product Design

Co-founder | Product Designer

2018 - 2021
FameUp
  • Validated product-market fit, strategically repositioning the product to align with market demands.
  • Implemented targeted user engagement strategies, elevating user retention rate from 3% to 24% by day seven (D7),.
  • Conducted comprehensive competitive analysis, identifying market gaps and opportunities to deliver unique value propositions.
  • Defined user experience strategy, integrating insights from internal teams and user research to enhance usability.
  • Developed high-fidelity prototypes and animations, facilitating clear communication of complex ideas and user flows to developers.
  • Designed a gamification system, leveraging a human-centric framework to drive key business metrics through core motivational drivers.
  • Reduced burn rate and optimized resources by creating a design system that enabled efficient and rapid implementation by the development team.
  • Analyzed and improved key business metrics, such as user retention, growth, and engagement, through iterative testing of core experiences.
  • Communicated product vision and strategic pivots to investors and co-founders, ensuring alignment on validated features and direction.
Technologies: UI Design, Figma, Interactive Design, Mobile UX Design, Validated User Research, Social Media, Mobile App Design, User Experience (UX), User Interface (UI), UX Research, Prototyping, UX Strategy, UX Design, Data Visualization, Adobe Creative Suite, Design Thinking, Material Design, Web App Design, Product Design, Early-stage Startups, Investments, Product-market Fit, Validation, Influencer Marketing, User Onboarding, User Flows, Startups, Gamification, Qualitative Research, Usability Testing, User Research, Design Systems, UI Audits, UX Audits, Photoshop CC, Digital Product Design, B2B

Co-founder | Lead UX/UI Designer

2015 - 2021
digitalmonks.co.uk
  • Led client discovery workshops, aligning business objectives, budgets, and product vision with a user-centered design approach.
  • Conducted in-depth competitive analysis, identifying gaps in crowded markets and uncovering opportunities for differentiation and unique value creation.
  • Defined and validated target user personas, leveraging customer discovery techniques, user research, and data-driven insights to refine product strategy.
  • Developed and tested product concepts, leading structured experiments using prototypes to validate the core utility and business model for clients.
  • Implemented UX funnels and engagement strategies, mapping desired user actions to business metrics, optimizing conversion rates, and improving retention.
  • Led cross-functional collaboration, working with developers, marketers, and stakeholders to translate business goals into functional, user-friendly digital experiences.
  • Advised clients on UX strategy and product positioning, bridging the gap between design, technology, and business growth for sustainable success.
  • Managed multiple projects simultaneously, ensuring high-quality execution and timely delivery while maintaining a strong focus on user-centered innovation.
Technologies: Adobe InDesign, Adobe Illustrator, Adobe Photoshop, Figma, UI Design, Interactive Design, Mobile UX Design, Validated User Research, Social Media, Mobile App Design, User Experience (UX), User Interface (UI), UX Research, Prototyping, UX Strategy, UX Design, Data Visualization, Adobe Creative Suite, Design Thinking, Material Design, Product Design, Early-stage Startups, Investments, User Onboarding, User Flows, User Research, UI Audits, UX Audits, Photoshop CC, Mobile Design

Lead Visual Designer

2012 - 2015
Respect Media
  • Designed original brand identities and digital and print assets from scratch, translating client specifications and market needs into compelling, high-impact visuals.
  • Managed end-to-end project execution, ensuring timely delivery, quality control, and seamless coordination between designers, developers, and stakeholders.
  • Led client consultations, aligning business objectives, budgets, and creative direction to deliver brand-consistent, results-driven digital experiences.
  • Developed high-quality digital and print materials, supporting websites, mobile applications, marketing campaigns, and product launches.
  • Supervised and mentored junior designers, fostering creativity and refining execution to uphold design excellence and consistency across projects.
  • Collaborated closely with developers and project managers, ensuring seamless translation of visual designs into functional, responsive digital products.
  • Researched and identified market trends, integrating modern design techniques, typography, and UI aesthetics into digital branding solutions.
  • Managed vendor and print production logistics, ensuring all ordered materials met quality standards and branding guidelines before final delivery.
  • Optimized workflow efficiency, implementing structured design processes that reduced turnaround time and improved client satisfaction.
Technologies: Adobe InDesign, Adobe Illustrator, Adobe Photoshop, UI Design, Interactive Design, Mobile UX Design, User Experience (UX), Adobe Creative Suite

Senior Graphic Designer

2011 - 2012
Bloom Communication
  • Met with clients to discuss their needs, objectives, and budgets.
  • Designed and created a wide variety of graphic art and promotional material.
  • Produced designs for internal and external communications.
  • Created integrated design projects across online and offline outputs.
  • Explained design concepts and ideas to clients and colleagues.
  • Worked on presentations, leaflets, trademarks, marketing materials, and banner designs.
  • Produced accurate and high-quality branding systems.
Technologies: Adobe InDesign, Adobe Illustrator, Adobe Photoshop, UI Design, Adobe Creative Suite

Graphic Designer

2010 - 2011
EXONIA HOLDING SA
  • Conceptualized, designed, and executed sophisticated print, merchandising, packaging, campaign, and branding experiences.
  • Researched creative trends in the industry, materials, processes, and competitive landscape.
  • Partnered and collaborated with copywriters to develop concepts with appropriate messaging implemented.
  • Collaborated with marketing management on creative concepts for campaigns and sales events.
  • Attended and participated in creative meetings regarding project status and follow-up actions.
  • Worked with print production requirements by working with external vendors from start to finish on projects such as printers, exhibit vendors, and other agencies.
  • Pre-flighted files included proofreading, performing quality assurance, and completing file delivery.
Technologies: Adobe InDesign, Adobe Illustrator, Adobe Photoshop, UI Design, Adobe Creative Suite

Graphic Designer

2008 - 2010
Freelance
  • Attended client meetings to understand the business objectives and client requirements.
  • Understood the client's needs and developed a concept that matches their requirements.
  • Interacted with the client on the concepts and got them approved.
  • Estimated the approximate time required to complete the work and provide quotes to clients.
  • Gathered information and data through research and developed design briefs.
  • Thought creatively and used innovative ideas to come up with new concepts and designs.
  • Presented the finalized work to the clients and took their feedback.
Technologies: Adobe InDesign, Adobe Illustrator, Adobe Photoshop, UI Design, Adobe Creative Suite

Education

2008 - 2011

Bachelor's Degree in Marketing

Alexandru Ioan Cuza University - Iași, Romania

Skills

Tools

Photoshop CC, Adobe Illustrator, Adobe Creative Suite, Miro, Maze, Adobe, Adobe Photoshop, FigJam, Adobe InDesign, Jira, Slack, Google Workspace, Adobe Experience Design (XD), Hotjar, Adobe CC

Languages

Visual Design Language

Platforms

Figma, iOS, Android, Music Streaming

Industry Expertise

Healthcare, Fitness, Health & Wellness, Investments, Sports, Restaurants & Dining

Other

Dashboards, Mobile Apps, Social Media Apps, Startups, Web App UX, User Flows, User Onboarding, Redesign, Web App UI, MVP Design, Influencer Marketing, Web UI, App Design, Design Systems, Web App Design, Design Thinking, Mobile App Design, Social Media, UI Design, Interaction Design (IxD), Interactive Design, User Experience (UX), Branding, Prototyping, Dashboard Design, Data Visualization, Mobile UX Design, Product Design, Visual Design, User Interface (UI), UX Design, UI Audits, UX Audits, Design Language, SaaS, B2C, Mobile Design, Web Design, Responsive Web Design (RWD), Networks, Google Design Sprints, Agile, Digital Product Design, B2B, Gamification, Chatbots, Validation, Product-market Fit, Platform Design, Subscriptions, Food Ordering, Online Shops, Optimization, Validated User Research, Sass, Early-stage Startups, Material Design, Qualitative Research, Usability Testing, User Research, Design Thinking Facilitation, Design Leadership, User Acceptance Testing (UAT), Fintech, UX Strategy, UX Architecture, UX Research, AI Design, Artificial Intelligence (AI), Healthtech, Notion, Web Dashboards, Responsive UI, Mobile UI, UI Pattern Library, Pattern Libraries, Atomic Design, Competitive Analysis, Competition Research, Enterprise System Design, System Design, UX Prototyping, Accessibility, Information Architecture (IA), Lifestyle, Behavioral Design, UI Components, Charts, React, Healthcare IT, Healthcare Software, User Testing, Web Platforms, Fintech Design, Onboarding, Online Payments, Marketplaces, Fitness Website Design, Wellness, Design Sprints, User Journeys, User Journey Maps, Wireframing, Web Components, Key Performance Indicators (KPIs), Business to Consumer (B2C), Lean Startups, Collaborative Design

Experience

  • Visual Design - 15 years
  • UI Design - 10 years
  • Mobile App Design - 8 years
  • UX Design - 8 years
  • Product Design - 8 years
  • User Research - 6 years
  • Data Visualization - 6 years
  • Figma - 5 years
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