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Hi! I’m a motion designer specializing in SaaS explainers created primarily in After Effects. Beyond my main focus, I have extensive experience producing targeted ads, content for LED screens, vertical videos, and various other animations. Additionally, I’m highly proficient in DaVinci Resolve for video editing and professional sound design. With a track record of working with over 400 clients — including banks and IT startups — I know how to deliver quality that fits your brand. My goal is simple: to make sure you’re thrilled with the final result so that we can work together again in the future.

🏆 𝗧𝗢𝗣 𝗥𝗔𝗧𝗘𝗗 𝗣𝗟𝗨𝗦 🏆 ✅ Mobile App Developer 7+ years of experience ✅ SaaS Mobile App Developer 5+ years ✅ 35 mobile app development jobs completed successfully ✅ Android and iOS Mobile Expert ✅ Built 27+ UX-first Mobile App development jobs for 22 companies ✅ On-Time and Cost-Effective Delivery ✅ Future-Proof Solutions Showing a Minimum 41% ROI ✅ 4354 mobile app development hours on Upwork and still counting ✅ 100% Job Success in mobile app development (Client Satisfaction Ratio) ✅ 98% of Clients Recommended working with me ✅ 80% Long-term Repeat Clients ✅ 7+ years of experience in mobile app development, 6 years experience in iOS mobile app development, 7 years experience in Swift and Kotlin, 4 years experience in Flutter, React Native, 2 years experience in KMM, KMP Full stack mobile app developer and mobile app UI UX designer with 7+ years of experience in Mobile App Development, specializing in iOS, Swift, Android, Kotlin, KMM, Kotlin Mutliplatform / KMP, React Native, and Flutter. I have successfully delivered 120+ mobile applications in different roles as mobile app developer, flutter app developer, flutter full stack developer, flutter flow, mobile app design, mobile ui ux designer, swift ios developer, android developer, kotlin developer, react native developer, mobile game developer achieving a 5-star rating on Upwork and helping clients scale their businesses with high-performance solutions. Apart from mobile app development, I specialize in Mobile App Design for both iOS and Android, as well as Web App Design for SaaS platforms. My expertise extends to Interaction Design, User Flow Design, and creating seamless User Experience (UX Design) and User Interface (UI Design). I follow a Design Thinking approach, ensuring every solution is user-centered and problem-solving. My process includes UI/UX Wireframing, Prototyping, and building Style Guides or UI-kits for consistent branding. I perform Design Audits and Design QA to maintain high standards across all projects. 🛠️ Design Tools: My designs come to life through powerful tools like Figma, Zeplin, and InVision for prototyping and collaboration. I leverage Adobe Illustrator, Adobe Photoshop, and Adobe XD for detailed visual design. For complex wireframes and flow mapping, I turn to Axure, Sketch, and Balsamiq. I also use Miro and Abstract for brainstorming and version control, while project communication and management happen in Slack and Jira. Our Expertise at a Glance • Mobile App Development: Android, iOS, & Cross-Platform App Development using Java, Kotlin, Swift, Objective C, Flutter, and more. • Website and Full Stack Development: Crafting seamless back-end experiences with .Net, Python, Java, Javascript, React.js, Angular.js, Node.js, MERN, MongoDB, PHP, etc. • Logo & UI/UX Design: Bringing your ideas to life with Adobe XD, Photoshop, Sketch, Figma, etc. • End-to-End Solutions: From logo design, UI/UX development, workflow setup, testing to deployment in app stores, we've got it all covered. We do not use v0.dev lovable.app CursorAI, Cursor, Windsurf, Trae, GitHub Copilot, Tabnine, Qodo, Devin AI, and AutoDev for speed up coding, we know other methods to do it efficiently. We offer a comprehensive range of development services across mobile, web, and cloud platforms. Our mobile app development expertise includes building Android and iOS applications using technologies such as Flutter, Swift, Objective-C, React Native, and Xamarin, optimized for both smartphones and tablets with a focus on cross-platform compatibility. In website and full stack development, we work with .NET technologies, including full stack .NET development, .NET Core, and Python with Django. Our team is experienced in developing both backend systems and user-friendly, responsive web interfaces, as well as working with various CMS platforms. Our DevOps and DevSecOps capabilities cover cloud infrastructure and automation, leveraging tools like AWS, Azure, Docker, Kubernetes, GitLab CI, Ansible, and Terraform to build secure and scalable deployment environments. We also build cross-platform and web applications using frameworks like Three.js and design tools such as Webflow, creating visually engaging and functional user experiences across devices. Additionally, we are well-versed in integration and automation tools, including WebSockets, data integration, the ABP Framework, Discord API, and Autotask, allowing us to create seamless connectivity and workflow automation between systems. Talent Good Knowledge, Talented, Experienced, Skilled, Strong Experience, Proven Experience, Agency, Team, Company, Specialist, Proven Track Record, Strong Background, Write Clean Code, Deep Expertise, Bring to Life, Cross-platform, Attention to Detail, Long Term. ⚡️ AVAILABLE FOR NEW PROJECTS ⚠️ Press Invite Button on my page and let's talk.

Hi! I am Dariusz, and I specialize in gamification systems. I have over 5 years of experience in designing and executing practical gamification strategies and over 15 years of commercial IT experience. With the support of my team, including talented Web & Mobile app developers, designers and Webflow specialists, I can help you transform your platforms into engaging, gamified experiences. 🧠 UNDERSTANDING THE HUMAN PSYCHOLOGY At the heart of my gamification philosophy is a profound understanding of human psychology. Successful gamification isn't merely adding points or badges – it's about leveraging innate human desires and motivations. I craft strategies that resonate with users, ensuring meaningful and lasting engagement. 🧑‍💻 WHAT CAN I HELP YOU WITH? ⚡ Gamification System Mechanics & Implementation ⚡ Crafting User Engagement Strategies through Gamification ⚡ Gamified UX/UI Design Consultation ⚡ Wordpress development ⚡ Team Collaboration & Productivity Enhancement ⚡ Insights on leveraging human psychology mechanics 🧑 WHAT CAN MY TEAM ASSIST YOU WITH? ⚡ Custom Web & Mobile Application Development ⚡ Webflow Design, Development & Optimization ⚡ Comprehensive UX/UI Design ⚡ SaaS Product Development & Optimization ⚡ Backend & Frontend Development for robust IT solutions 🎨 SELECTED WORK ▶️ Ogamify (Gamification System for Teams) - ogamify.com A comprehensive solution designed to gamify team interactions, enhancing productivity and collaboration. ▶️ The "Real-Life Gamification" book that I wrote to summarise my experiences. Feel free to reach out for a free copy! ▶️ My blog at dariusztarczynski.com where I share gamification tips, if you are looking for some fresh gamification ideas! ❓WHY PARTNER WITH ME? ✅ Gamification Expert: With my unique blend of technical expertise and psychological insights, I promise gamification strategies that truly engage and resonate. ✅ Full-Suite Team: With a handpicked team of specialists, from designers to developers, I offer end-to-end services, ensuring a seamless gamification experience. ✅ Two Decades of Experience: My vast experience in the IT realm ensures that your projects benefit from proven strategies and top-notch execution. ✅ Unparalleled Quality: My work speaks volumes. I'm committed to ensuring your platforms not only function perfectly but also captivate your users. 💬 CONSULTATIONS 💻 Gamification Strategies & Implementation 💻 Custom Web & Mobile Application Development 💻 Team Collaboration through Gamification 💻 UX/UI Design for Gamified Platforms

Hello! I’m Polina, a Senior Product Designer and the CEO of Phenomenon Studio. 📣 I lead our team in creating innovative and user-centric solutions that transform ideas into successful products. Starting as a small startup, we have grown into an international company capable of handling projects of any complexity. 🏆 While our primary focus is on product design and development, we also offer select promo services like branding and web design to ensure a cohesive and compelling experience for our clients. Website: phenomenonstudio.com Dribbble: dribbble.com/phenomenonstudio Behance: behance.net/phenomenon-studio If you're looking for a partner to bring your product vision to life from concept to launch, we’re here to help you succeed🔥