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Tomislav Krnic
Verified Expert in Engineering
Full-stack Developer
Tomislav is a full-stack developer and designer with over 20 years of experience. He has recently focused on React Native mobile development and real-time databases. He has founded or co-founded six businesses with three successful exits. He prides himself on a proven record of building full solutions with tangible results.
Portfolio
Experience
Availability
Preferred Environment
React Native, Firebase, User Interface (UI), Startups, Unique Business Ideas, CSS, Full-stack, UI Design
The most amazing...
...ability I have is that I can turn a basic business idea into a functional and understandable project that users know how to use.
Work Experience
Founder
CityX Apps
- Acted as the founder and CTO of CityX, a company specializing in smart city app solutions. The app is available in over 50 cities and 12 countries and has been translated into 10 languages. The app consists of a collection of APIs and open data.
- Found answers to questions on how to make the biggest app in a smart city space. Brought the idea to life, including contributing to designing the system architecture, leading developers, and creating the entire UI/UX.
- Delivered the CityX app, a fully functional application available in stores. Many AI solutions have reduced the need for an oversized team. Quarterly growth is approximately 200%.
- Utilized my skills, encompassing React Native, Firebase, React, Node.js, UI/UX, Google Cloud, payment solutions, tons of API integrations, and cloud functions.
- Created an MVP app that serves as a solunar forecast for anglers and has an integrated map with the option of live streaming fishing and positions. With integrated AI, the application recognizes the type of fish from the photos.
Full-stack Developer - React Native Mobile
Yahn Enterprises, LLC
- Developed a mobile application within the planned timeframe, from a client's idea into a fully functional product ready for user acquisition.
- Performed full-stack development, UI/UX, and logo design.
- Built the application with React Native and Firebase. The app is published in App Store.
Full-stack Mobile Developer
Entrio
- Developed a mobile app from Entrio, the most prominent Croatian event-ticketing company with over 1,200 events per year and over 280,000 tickets.
- Built a React Native application from scratch that was intended as a ticket scanner connected to a few servers with non-SQL and SQL databases.
- Contributed to developing the React Native application that consisted of multiple solutions, including communication between scanners, offline mode, and tons of logs. Event organizers could hire Entrio to ensure a smooth process.
Co-founder | CTO and Full-stack Mobile Developer
Grga
- Worked on Grga, a mobile application for payment and ordering processes related to restaurants and bars. The app provides a solution for connecting to more than 50,000 cash registers. One solution enables users to make orders and pay with a QR code.
- Designed a system, created a mobile app and the UI/UX and connected with the payment gateway. Worked on it for a little over two years; millions were paid without any mistakes or wrong orders, and I have a reason to be satisfied with the project.
- Completed the project and after a successful exit, Grga still exists within a large multinational company.
Co-founder and Senior Full-stack Developer
Touchmoon
- Created an application for Touchmoon, a demanding project that aimed to represent a new generation of mobile messengers. The application has multiple unique solutions and features like animations, strong security, and custom games.
- Created the functional UI/UX and the web part of the project.
- Delivered Touchmoon, the app had a good start, excellent reviews, and was mentioned in the media.
Senior Front-end Developer
FragranceX
- Developed the front end and responsive design as my role for the project.
- Worked for FragranceX, one of the biggest US-based eCommerce stores. Every "pixel" on the web was important, and my focus on details came to the fore.
- Optimized the user interface and experience; developed the JavaScript front-end solutions and created a fully responsive web.
Senior Front-end Developer
LogoGarden
- Designed and developed the company website and improved the UI/UX for responsive websites.
- Utilized technologies, including HTML, CSS, jQuery, JavaScript, and Sass, for the project.
- Built LogoGarden, an online logo creation for your business with over 2.5 million custom logos made. Users can create their logos fast and for free.
Senior Front-end Developer
Rock Lobby (via Toptal)
- Developed a custom CMS solution.
- Developed UI/UX elements using jQuery.
Front-end Developer
Rise Events (via Toptal)
- Developed four websites for this Washington D.C.-based real estate company.
- Designed four connected web pages based on the same style with small variations.
- Created a jQuery/GoogleMap system to display location on mouseover.
Front-end Developer
Eminent Domains/IMissYou (via Toptal)
- Created a strong and user friendly front-end with many jQuery features.
- Built a beautiful but technically complex layout with a combination of photos/videos/Twitter/Facebook/message and models put in masonry composition.
Senior Web Developer
Design Theorem/oMiami (via Toptal)
- Handled project finalization to solve problems with connecting scrolling events and pointing places on maps.
- Took care of various advanced CSS tasks.
Owner, Senior Web Developer (Code and Design)
Studio Cro-Design
- Created a photo community site independently with over 13,000 users in the Croatian photography community. Received numerous recognitions and included over 800 themed competitions. Looked into expanding the site to the US market.
- Created a B2B image sharing system for Mars, a large food distribution company. Designed initially for Mars Croatia, but later expanded to Mars Europe. Included automated image preparation, zip file creation, and download management.
- Developed a CMS for a real estate agency, including multi-language support and a best property search features.
- Wrote a fully automated system that used Expedia API for booking hotels and flights.
- Created a small corporate web page with a clean design displaying a simple, custom CMS and moderate use of jQuery and Flash.
Co-founder, Web Project Manager, Senior Developer
iKiosk
- Developed a system independently for formatting and selling digital magazines, books, and newspapers. Won recognition from Forbes magazine as a great internet business project.
Experience
Touchmoon Messenger
I acted as a co-founder for this project, developing front- and back-end services, app games, and many other features that I created over 3+ years of hard work.
Grga - Mobile Ordering and Payment App
http://grga.euI acted as the co-founder and full-stack mobile developer for a mobile payment app available in many cafes in Croatia. The application is in the top 10 of the App Store, with over 100 stores and 9,000 users.
TECHNOLOGIES AND APPLICATION CHARACTERISTICS:
• React Native
• Redux
• API
• Cash register connection
• Payment system (accepting all major credit cards)
• QR reader
• Firebase authentication, messages, analytics, function/back-end
• Notifications
• API Connect
• UI/UX
• App Store and Google Play
Apps.apple.com/hr/app/grga-tvoj-digitalni-konobar/id1439087229?l=hr
Play.google.com/store/apps/details?id=com.grga&hl=e
Undiet Tracker
• React Native
• Redux
• Firebase DB/storage, authentication, messages, analytics, function/back end
• Notifications
• UI/UX
• App Store and Google Play
• Landing page
Development time: 25 days
The app is available at:
• https://apps.apple.com/us/app/undiet-tracker/id1490849895?ls=1
• https://play.google.com/store/apps/details?id=com.undiet&hl=en
AirQuality and Weather Chat
https://apps.apple.com/us/app/airquality-and-weather-chat/id1495791987?ls=1• Live weather data, 200,000 cities
• Chat, based on the nearest measuring station
• React Native
• Redux
• Firebase authentication, messages, analytics, function/back end
• Notifications
• API connect
• UI/UX
• App Store and Google Play
• Landing page
Development time: 20 days
Fishing Pro App
https://fishingpro.cityx.hrA notable innovation is the AI-enabled fish recognition tool, which provides details like size, weight, and catch difficulty. My role extended to integrating in-app purchases and subscriptions, leveraging 3rd-party services for improved sales efficacy, and overseeing the app's UI/UX design to ensure a user-friendly experience. Using Redux and Firebase, the app was developed as a robust MVP, blending technology with the outdoor fishing adventure.
Skills
Languages
PHP, HTML5, Sass, CSS, JavaScript, SQL, TypeScript, CSS3
Frameworks
React Native, Redux, Smarty
Libraries/APIs
jQuery, API Development, React, REST APIs, Mapbox API, Google Maps, Facebook API, Twitter API, Amazon FPS, Node.js, Google Maps API
Tools
Adobe Photoshop, Adobe Illustrator, Figma
Paradigms
UX Design, Mobile Design, UI Design, Mobile Development, Cross-platform
Platforms
Firebase, Google Cloud Platform (GCP), Mobile, Mapbox, iOS, Android, Amazon Web Services (AWS)
Industry Expertise
Web Design
Storage
JSON, MySQL, Firebase Realtime Database, SQLite
Other
Pixel Perfect, Graphic Design, Ajax, User Interface (UI), Icon Design, APIs, Web Development, Front-end, Front-end Development, User Experience (UX), Software Development, Full-stack, Startups, Card Payments, Payment APIs, Credit Card Processing, Design, Development, Scanning, Ticketing, Ticket Systems, Events, Event Ticketing, Minimum Viable Product (MVP), Web & Mobile Applications, Mobile App Development, Mobile UI, Mobile UX, Push Notifications, Mobile Applications, Startup Consulting, ChatGPT, OpenAI, App UI, App UX, Full-stack Development, Live Chat, Artificial Intelligence (AI), Maps, Unique Business Ideas
Education
Bachelor's Degree in IT Engineering
Polytechnic University of Zagreb - Zagreb, Croatia
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