Dániel Rózsa, Developer in Szeged, Hungary
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Dániel Rózsa

Verified Expert  in Engineering

Mobile App Developer

Szeged, Hungary
Toptal Member Since
June 18, 2021

Dániel is a software developer with seven years of experience. He started his career in Java and Kotlin Android development, began freelancing in 2019, expanded into full-stack development with Laravel and React, and currently specializes in developing Android, iOS, and web apps, using Flutter. Dániel has developed a wide range of cross-platform apps, including language learning, construction project management, an e-car charging station finder, and an allergen-free food finder.


Theheard, Inc
Flutter, Firebase, APIs, Android, iOS, Firebase Hosting, Cross-platform
Flutter, Firebase, Firebase Hosting, Cross-platform, Stripe, Subscriptions...
DappWall GmbH
Flutter, Android, iOS, Cross-platform, Mobile Apps, Android Studio...




Preferred Environment

Flutter, Android, Slack, Git, Full-stack, Firebase

The most amazing...

...apps I've developed were based on my own ideas, acknowledged by the media in Hungary, and expanded my areas of expertise.

Work Experience

Flutter Expert

2022 - 2022
Theheard, Inc
  • Fixed critical performance, memory, and UI issues in the existing codebase.
  • Refactored the application to improve stability and performance and enable faster development and release cycles.
  • Helped the team to select the proper third-party analytics tools to define analytics events, reports, and funnels.
  • Developed and hosted an admin dashboard where the team could see and manage the application data.
Technologies: Flutter, Firebase, APIs, Android, iOS, Firebase Hosting, Cross-platform

Senior Flutter Developer

2021 - 2021
  • Ported existing iOS applications for Android, iOS, and web written in Flutter.
  • Implemented Firebase with real-time updates to support fast collaboration on managing projects.
  • Added a client-side PDF generation, which contains various content.
  • Implemented a Stripe API on the web for a metered-billing monthly subscription.
  • Connected to the QuickBooks API to create invoices and bills.
Technologies: Flutter, Firebase, Firebase Hosting, Cross-platform, Stripe, Subscriptions, QuickBooks API, PDF

Mobile Developer

2020 - 2021
DappWall GmbH
  • Played a key role in building the Skeebdo startup project, a language learning app with gamification and fun content.
  • Developed the cross-platform app for iOS and Android, using Flutter technology.
  • Managed the entire process to develop the application.
Technologies: Flutter, Android, iOS, Cross-platform, Mobile Apps, Android Studio, Software Development, Dart, Push Notifications, Gradle, Slack, Git, Clean Architecture, Model View ViewModel (MVVM)

Full-stack Developer (Contract)

2019 - 2021
Lokcheck Kft.
  • Created a cross-platform project management tool that's designed for construction companies.
  • Solo-developed the company's app, including setting up and managing the server. The mobile app and the website were made with Flutter.
  • Solved challenging tasks, such as converting drawing markups to PDF.
Technologies: Flutter, Dart, Laravel, PHP, Cross-platform, Full-stack, Mobile Apps, Software Development, Unit Testing, Android, Jenkins, Push Notifications, Gradle, Slack, Git, Clean Architecture, Android SDK, Model View ViewModel (MVVM), Jira

Scrum Master and Team Lead

2017 - 2019
CAS Software Kft
  • Learned Agile methodology and successfully guided a team of seven people through a project.
  • Gained Scrum Master I and Scrum Master II certifications from Scrum.org.
  • Introduced new technologies and methods to my teams, such as Kotlin, RX, and TDD.
  • Collaborated with the product owner to improve development processes.
Technologies: Agile, Android, Scrum Master, Kotlin, Jira, Scrum, Agile Software Development, Certified ScrumMaster (CSM), Software Development, Android Studio, Test-driven Development (TDD), RxAndroid, RxJava, Unit Testing, Jenkins, Android Data Binding, Push Notifications, Gradle, Slack, Git, Clean Architecture, Android SDK, Model View ViewModel (MVVM)

Android Developer

2014 - 2017
CAS Software Kft.
  • Developed a business card reader app in native Android.
  • Assisted in developing several native Android apps, including an e-car charging station finder and a newsreader.
  • Participated in research projects, such as an augmented reality application.
Technologies: Android, Java, Jira, Agile Software Development, Agile, Mobile Apps, Android Studio, Software Development, Kotlin, RxJava, RxAndroid, Jenkins, Push Notifications, Gradle, Git, Clean Architecture, Android SDK, Model View Presenter (MVP)


Freezon is a service, including an Android app and a website, that collects the world's restaurants, bakeries, cafés, confectioneries, and shops where people living with allergies and intolerances or who follow special diets can find allergen-free foods, drinks, and goods. My wife and I created the concept and implemented the service ourselves.

Buddy Block Buster

A slide-puzzle-styled game on the Android platform, created with Unity. My wife and I created the concept and worked together to design the story, gameplay, and UI, and develop the game. This was a purely fun project to learn and apply new skills and realize the idea for the game.


Lokcheck is a project management tool designed for construction companies. With this cross-platform service, clients can create schedules, custom documents, and inventories, and track costs with their teams on iOS, Android, and web. Companies can boost scheduling and internal documentation while creating transparency. With Lokcheck, documenting processes is faster and available everywhere, helping companies monitor their projects more easily.

As a full-stack developer, I developed the app and created and managed the server. I also took part in brainstorming sessions to invent and create new functions.
2012 - 2015

Bachelor's Degree in Software Engineering

University of Szeged - Szeged, Hungary


Professional Scrum Master II



Professional Scrum Master I



RxJava, React, Stripe, QuickBooks API


Android Studio, Jira, RxAndroid, Git, Slack, Gradle, Jenkins


Flutter, Android SDK, Laravel, Unity


Clean Architecture, Scrum, Cross-platform, Agile Software Development, Agile, Test-driven Development (TDD), Unit Testing, Model View ViewModel (MVVM), Model View Presenter (MVP)


Kotlin, PHP, Java, Dart, C#


Android, Firebase, iOS


Software Development, Mobile Apps, Mobile App Development, Mobile Applications, Scrum Master, Full-stack, Certified ScrumMaster (CSM), Web Development, Push Notifications, Android Data Binding, Minimum Viable Product (MVP), Deployment, App Store, Google Play Store, Firebase Hosting, Subscriptions, PDF, APIs

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