Jürgen Koller

SwiftUI Software Developer

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Heilbronn, Germany

Experience

Jan 2023 - Present
3 years 1 month

SwiftUI Software Developer

  • Successfully implemented the entire macOS app 'PDF Content Search' and the iOS app 'PDF Cnt Search' from initial concept to final release in the App Store.
Jan 2022 - Dec 2022
1 year

Swift Software Developer

  • Developed a utility app for macOS using Xcode and SwiftUI
  • Technologies used: OCR, SQLite, cloud services, SwiftNIO
  • Published the 'PDF Content Search' app on the Apple macOS App Store
Jan 2021 - Dec 2022
2 years

Xamarin Frontend Developer

  • Member of a Scrum team developing an app for accessing household appliances
  • Implemented user stories for cloud features via an external cloud service
Jan 2020 - Dec 2021
2 years

Xamarin Software Developer

  • Collaborated in a 9-person team (frontend, backend, QA, UI/UX) using agile Scrum
  • Implemented all pending user stories into a Xamarin Forms Shell application for iOS and Android
Jan 2019 - Dec 2020
2 years

Xamarin Software Developer

  • Sole developer responsible for the entire development and release process of a Xamarin app update with native UI for iOS and Android
  • Collaborated with a UI designer and project manager
Jan 2018 - Dec 2019
2 years

Xamarin Software Developer

  • Developed a new mobile client for SAP systems with Xamarin.Forms (iOS, Android)
  • Supported a team of 5 .NET developers in creating a dynamic XAML UI powered by Entity Framework
Jan 2018 - Dec 2018
1 year

Xamarin Software Developer

  • Migrated an Android app to Xamarin with a shared codebase for Android and iOS
  • Applied MVVM, mobile services, data persistence, and Bluetooth communication
  • Responsible for the full development cycle as lead developer
Jan 2017 - Dec 2017
1 year

Xamarin Frontend Developer

  • Brought Xamarin knowledge into a .NET team (frontend, backend, QA, UI/UX) using agile Scrum
  • Business domain: Augmented Reality Remote Service
  • Technologies: Xamarin, C#, Xamarin.Forms, Visual Studio, Visual Studio for Mac, iOS, Android, Windows UWP
Jan 2016 - Dec 2016
1 year

Xamarin Software Developer

  • Added new features and fixed bugs in an existing Xamarin Android app with native UI
  • Business domain: Sports and Leisure
  • Technology: Xamarin C#, Xamarin Studio, Android
Jan 2016 - Dec 2016
1 year

Xamarin Software Developer

  • Built a new Xamarin app from scratch with native UI for iOS and Android
  • Integrated backend and background services like GPS tracking
  • Business domain: Logistics and Transport
  • Technology: Xamarin C#, Xamarin Studio, iOS, Android
Jan 2016 - Dec 2016
1 year

Xamarin Software Developer

  • Porting a native Windows Phone app to Xamarin with support for iOS, Android and Windows Phone
  • Planning and executing the app transfer as the sole developer within the given time and budget constraints
  • Business area: Logistics and Transportation
  • Technology: Xamarin C#, Xamarin Forms, Xamarin Studio, Visual Studio, iOS, Android, Windows Phone, SQLite, RESTful service
Jan 2015 - Dec 2015
1 year

Xamarin Software Developer

  • Connecting an existing Xamarin Android app to a new backend REST API service
  • Business area: Sports and Leisure
  • Technology: Xamarin C#, Xamarin native UI, Xamarin Studio, Android, RESTful service, ServiceStack, mopub
Jan 2015 - Dec 2015
1 year

Xamarin Software Developer

  • Developing a new Xamarin iOS/Android app for citizens to contact government officials
  • Business area: Citizen Services
  • Technology: Xamarin C#, Xamarin Forms, Xamarin Studio, Android, iOS, RESTful service, Azure push notifications
Jan 2014 - Dec 2014
1 year

Xamarin Software Developer

  • Developing a Xamarin iOS, Android and Windows Store app for BORT medical with 100% offline functionality for product news
  • Client: BORT GmbH, Germany
  • Business area: Medical Healthcare
  • Technology: Xamarin C#, Xamarin native UI, Visual Studio, Xamarin Studio, SQLite, custom data synchronization, offline HTML layout rendering
Jan 2011 - Dec 2013
3 years

Mac Objective-C Developer

  • Developing a native macOS app in Objective-C for peer-to-peer data transfer without a cloud service
  • Business area: Tools and Utilities
  • Technology: Xcode, Objective-C, CocoaAsyncSocket
Jan 2011 - Dec 2013
3 years

Mac & iOS Objective-C Developer

  • Developed a native macOS app in Objective-C for photo professionals to easily share photos via smartphones
  • Developed the macOS server application MyPicServer and the client app MyPic
  • Industry: Utilities
  • Technology: Xcode, Objective-C
Jan 2011 - Dec 2012
2 years

Mac & iOS Objective-C Developer

  • Developed a new iOS app for BORT medical with 100% offline functionality for product news
  • Industry: Healthcare
  • Technology: Xcode, Objective-C

Summary

Xamarin / SwiftUI software developer with 13 years of experience in developing mobile applications and 10 years of experience with Xamarin technology.

Skills

  • Swift
  • Swiftui
  • .Net Maui (Xamarin)

Languages

German
Native
English
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