Welcome! I am a software developer focused on building high-performance, user-centric applications for the Apple ecosystem. This repository serves as a showcase of my published work in the App Store.

While the source code for these projects is proprietary, I have provided technical overviews and architecture highlights for each application below.

The ultimate running companion for Apple Watch & iPhone.

MetroPacer is an "offline-first" fitness application designed to provide real-time tracking of pace, cadence, heart rate, and distance. It allows runners to hit specific goals through guided workouts with spoken feedback.

• Offline-First Architecture: Designed to handle data reliably even in areas with poor cellular connectivity, ensuring no workout data is lost.
• Core Data & Synchronization: Leverages Core Data for local persistence, with a robust sync engine to bridge data between the Apple Watch companion and the iPhone app.
• Reactive UI: Built using Combine to handle real-time sensor data streams and provide immediate UI feedback during high-intensity runs.
• HealthKit Integration: Seamlessly reads and writes health metrics while respecting user privacy and system permissions.

metropacer.com | View on App Store

Professional Image Editor for macOS.

Diffraction is a comprehensive image editing suite tailored for creative professionals. It features a custom image processing core capable of handling complex compositions with layers, masks, and AI-driven tools.

• Custom Framework Structure: Built with a modular architecture, separating the UI layer from the ImageCore (processing) and IO (file management) modules.
• Advanced Image Processing: Implements classic and modern image processing algorithms, including color correction (Curves, Levels), blurring, and distortion filters.
• AI-Powered Tools: Features intelligent subject masking and spot removal, utilizing machine learning to simplify complex retouching tasks.
• High Performance & Stability: Includes an extensive suite of Unit Tests for core modules to ensure stability when processing large, multi-layered PSD and HEIC documents.
• Apple Silicon Optimized: Fully optimized for M1/M2/M3 chips to ensure near-instant rendering of effects.

schubert-it.com/diffraction | View on Mac App Store

• Languages: Swift, Kotlin, Objective-C
• Frameworks: SwiftUI, AppKit, UIKit, WatchKit, Combine, Core Data, HealthKit, Core Image
• Tools: Xcode, Git, XCTest (Unit & UI Testing), IntelliJ IDEA
• Focus: Clean Architecture (MVVM/MVC), Performance Optimization, User Privacy

Contact: manfred@schubert-it.de