Verified Expert in Engineering
Material Design Developer
Krystian is a versatile programmer with a focus on Android development. He offers comprehensive Android development services. Krystian can take a project from the initial idea to launching the app to the Google Play Store and handling long-term maintenance and future growth.
IntelliJ IDEA, Android Studio
The most amazing...
...thing I've worked on is a social video app, during its growth as one of the leaders in its market.
- Introduced new features into a social video app with over 100 million downloads.
- Developed advanced video editing functionality, such as filters and video clip composition.
- Helped transition Java MVP architecture to Kotlin MVI.
- Participated in a well-organized and mature Scrum process.
Freelance Full-stack Android Developer
- Acted as the lead Android developer on a white-label carsharing app with hundreds of thousands of installations across Europe and Asia.
- Worked as the Android developer on a platform that expedites home delivery from local businesses.
- Developed an MVP for an app that allows users to view marketing content to collect points, then spend them on ad-free usage in the apps of partnering businesses.
- Built an Android app for website-sharing social, video-based smartphone reviews.
- Developed an app for users inexperienced with social media, that facilitates exchanging wishes between friends and family on birthdays, anniversaries, and other life events.
- Built an Android app for a security contractor to streamline writing collaborative security assessment reports for their employees, annotating them with editable images, videos, and maps; as well as geospatial information.
- Constructed an MVP Android app and web-based administration tools for a platform that facilitates buying, selling, and exchanging clothing items.
- Designed an Android app that allows users to coordinate menus for dinner parties.
- Built an Android application for placing client orders and monitoring delivery progress.
- Developed an Android application for assisting delivery drivers with order contents and navigation.
- Redesigned a company's website and online ordering system.
- Developed desktop software to generate and print customer invoices.
- Built a type of desktop software to facilitate employee management.
- Automated synchronizing orders with third-party order and delivery services.
- Redesigned intranet web tools for restaurant management.
- Automated email and text message promotional campaigns.
University of Wisconsin-La Crosse
- Automated the deployment of Cisco routers and computer network configurations.
- Installed and maintained fiber-optic and copper cabling.
- Performed remote and on-site diagnostics of networked devices.
- Developed and maintained the networking department's web page.
- Built a centralized build server to replace individual build servers used by seven teams on site.
- Designed an intranet web page to display build results for all teams.
- Automated nightly builds along with sending build reports to team managers.
As the lead Android developer, I implemented new features such as support for multiple map providers and payment processing, rebranded the app for individual client companies, and performed general maintenance tasks.
As the developer for the Android app, I worked with Google Maps, Mapbox navigation, communicating with the Firebase backend, and implemented a visual redesign of the app.
FireWatch Solutions (Internal-use App)https://www.firewatchsolutions.com/
Over the years, I have implemented new features, app redesigns, and performed general maintenance.
Among other things, I have built their back end, website, and matching Android app. The whole set spans numerous platforms, including Windows and Unix servers, a variety of databases and communication protocols and web- and Android-based client apps.
RxJava 2, Google Location API, Google APIs, Google Maps SDK, Google Drive API, Node.js, Facebook API, OpenStreetMap API, Yelp API, WhatsApp API, Accelerometers
Android Studio, Visual Studio, IntelliJ IDEA, Perforce, Apache Ant, JWPlayer, Branch.io
Model View Presenter (MVP), Model View Viewmodel (MVVM), Reactive Programming, Model View Intent (MVI), Test-driven Development (TDD), Continuous Integration (CI), Scrum
Android, Firebase, Google Cloud Platform (GCP), Google App Engine, iOS
Firebase Realtime Database, MySQL, SQLite, Realm, MaxDB, Cloud Firestore
Full-stack, Mobile App Development, GPS, Video & Audio Processing, Video Streaming, Material Design, AdMob, Cisco, Room, Near-field Communication (NFC), Mapbox SDK, Mobile Payments, Bluetooth
ASP.NET, Dagger 2, Flutter
Bachelor of Science Degree in Computer Science, Mathematics, Physics
University of Wisconsin-La Crosse - La Crosse, WI, USA
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