Streak Finder

Streak Finder

Native iPhone + Apple Watch app that mines your Apple Health history for the fitness streaks you've already built — the ones you didn't realize were going — and nudges you to keep them alive.

• Discovery engine. Automatically finds active streaks across steps, exercise minutes, stand hours, active energy, workouts, mindfulness, sleep, distance, and flights climbed — at every threshold tier, daily and weekly.
• Hero streak + badges. One flagship streak front and center, with the rest as tappable badges.
• Strict daily, with weekly fallback. If your daily streak breaks, a weekly streak keeps the momentum alive.
• Calendar heatmap per streak, showing every hit and miss in the last year.
• Home + Lock Screen widgets. Small, medium, and lock-screen complications.
• Apple Watch. Full watch app plus circular, rectangular, corner, and inline complications.
• Daily at-risk reminder. 7pm nudge if the hero streak isn't locked in yet.
• Local-only. Read-only HealthKit access. No network, no analytics, no accounts.

Tech

• Swift 6 / SwiftUI, strict concurrency
• HealthKit (read-only)
• SwiftData (local cache, shared via App Group)
• WidgetKit (iOS + watchOS)
• XcodeGen (project.yml → .xcodeproj)
• iOS 17+ / watchOS 10+

Build

# Requires: brew install xcodegen
xcodegen generate
open FitnessStreaks.xcodeproj

Or from CLI:

xcodebuild -project FitnessStreaks.xcodeproj \
  -scheme FitnessStreaks \
  -destination 'generic/platform=iOS' build

TestFlight

./scripts/testflight.sh

Requires Xcode signed in (Settings → Accounts) with team YXG4MP6W39.

Architecture

Four targets, all sharing Shared/:

App group: group.com.jackwallner.streaks

Shared/

• Models/StreakMetric.swift — enum of metrics + per-metric threshold ladders + display.
• Models/Streak.swift — Streak (current/best/threshold/progress) + ActivityDay.
• Models/DailyActivity.swift — SwiftData @Model cache row.
• Services/HealthKitService.swift — HK auth, daily history fetch across 9 metrics, background delivery, SwiftData upsert.
• Services/StreakEngine.swift — the core. Scans history and picks, per (metric, cadence), the highest-threshold tier with an active streak — daily and weekly. Ranks by an interestingness score.
• Services/StreakStore.swift — @MainActor ObservableObject that drives the iOS + watch UI.
• Services/StreakSettings.swift — user prefs + SnapshotStore that persists the top streaks to App Group UserDefaults so widgets can render without hitting HealthKit.
• Services/DataService.swift — SwiftData container scoped to the app group.
• Services/NotificationService.swift — daily 7pm at-risk reminder.
• Utilities/Theme.swift, Utilities/DateHelpers.swift.

How the engine discovers streaks

1. Pull ~400 days of daily samples from HealthKit (sum-per-day for quantity types; workout counts for HKWorkout; sleep attributed to the day each asleep sample ended on).
2. For each metric (9 of them), evaluate every threshold tier (e.g. steps → 3k/5k/7.5k/10k/12.5k/15k) at both daily and weekly cadence.
3. Pick the highest threshold per (metric, cadence) with current ≥ minLength (3 days / 2 weeks).
4. Rank with score = length × metricWeight × tierBonus. The top one is the hero; the rest are badges.
5. Today (or this week) doesn't break the streak until it ends — the live unit counts once the threshold is met.

Privacy

• Reads only. Never writes to Apple Health.
• No network calls. No third parties. No analytics.
• All data stays on-device + in the app group container.

License

Personal project.