iOS · Native Swift2026
HabitLoop
Privacy-focused iOS habit tracking app built with SwiftUI, Core Data, WidgetKit, and modern Swift concurrency. Features algorithmic pattern detection, weekly AI reflections via Apple FoundationModels, interactive Home Screen widgets, and zero external dependencies.
- Role
- iOS Engineer — Architecture, Core Data, WidgetKit, AI Reflections
- Timeline
- 2026 · Open Source
- Stack
- SwiftUICore DataWidgetKitAppIntentsSwift ConcurrencyObservationXCTest
01
Screens & Architecture
02
The Problem
Most habit trackers rely on cloud sync, external analytics, and subscription paywalls. I wanted to build a 100% native, privacy-first iOS app with zero third-party dependencies that runs entirely on-device.
03
How I built it
- Built the entire app using only Apple-native frameworks — SwiftUI, CoreData, WidgetKit, UserNotifications, AppIntents, Foundation — with zero external dependencies.
- Engineered algorithmic pattern detection: weekday vs. weekend gap analysis, peak time-of-day bucketing, and proactive streak risk alerts based on historical completion windows.
- Integrated Apple FoundationModels (iOS 18.1+) for weekly on-device AI reflections with deterministic fallback summaries cached in Core Data.
- Designed interactive Home Screen widgets (systemSmall + systemMedium) with AppIntents allowing users to toggle habits directly from the Home Screen.
- Built a shared Core Data persistent container via App Group for real-time data sharing between the main app and WidgetKit extensions.
04
Outcome
- 100% native iOS app with zero third-party dependencies.
- Comprehensive XCTest suite covering Core Data CRUD, streak calculations, pattern insights, and widget intents.
- Interactive WidgetKit widgets with live habit toggling via AppIntents.