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Mobile Systems Engineering · Native iOS Studio

Shipped to the Pocket.

Native iOS and mobile systems designed, built, and deployed to production by Benjamin Sachwitz under BFS Development LLC. Engineered for tactile touch UI, ProMotion 120Hz frame rates, offline-first data persistence, and zero background battery drain.

2 Shipped to App Store 1 Production Chapter Mobile 0 Third-Party Ad Trackers 120Hz ProMotion Tuned
44pt Touch Targets

Calibrated to Apple HIG standards. Every button and interactive control guarantees zero miss-taps.

< 8.33ms Frame Budget

ProMotion 120Hz spring physics without frame drops or jitter on iPhone Pro Super Retina displays.

Zero-Leak Battery

0.0% background battery drain. Zero background location poller threads or zombie listeners.

Encrypted On-Device

Local SwiftData and IndexedDB caching ensure instant launches even in offline transit modes.

Bar Crawl Golf iOS App Scorecard
Live · App Store
/ 01

Bar Crawl Golf.

Your crawl, your rules. Group competition turned into a real party game. Set the course, score the holes, settle the night. Shipped natively to iPhone.

iOS Native SwiftUI Multi-Player Haptics
Interactive Site → Web →
Greekstack Chapter Mobile App Interface
Mobile App · Production
/ 03

Greekstack App.

The companion mobile experience for Greek life. Instant prospective member check-ins, active brother bid scoring, dues payments with Apple Pay, and secure voting.

iOS App Rush Intake Apple Pay Live Voting
Launch Your Chapter
Parent Entity · Software Studio
BFS Development LLC - Vintage Retro Cream Logo

BFS Development LLC.

The independent software development studio founded and solely owned by Benjamin Sachwitz. BFS Development LLC (bfsdevelopement.app) serves as the official legal and operational foundation for native iOS applications, multi-player party games, and community SaaS platforms.

Official Site: bfsdevelopement.app → Studio Privacy Commitments
Shipped Apps
2 Live
Apple App Store
Chapter OS
1 Active
Production SaaS
Telemetry Policy
0 Trackers
Private On-Device
Monetization
0 Ad SDKs
Clean User Experience
Under The Hood · Mobile Engineering

Architecture & Engineering Deep Dive.

How these products are built from scratch. Explore the technical stack choices, state persistence loops, and native iOS hardware integrations across the portfolio.

Native Swift 5 · iOS 17+ Target

Zero-Latency On-Device Architecture

My Daily Tool was engineered around a strict human design axiom: Open the app. See your entire day without a single scroll. Leave. To guarantee instantaneous launch times, the app relies on zero external API calls for its core loop.

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SwiftData & CoreData Bridge: All 22 milestone tracking items, calorie inputs, and habit streaks persist locally on the device with encrypted disk storage.
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Apple HealthKit Integration: Direct read permissions for active energy burned and step counts, rendered natively on a synchronized multi-ring canvas.
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ProMotion 120Hz Animations: Fluid spring-physics transitions calibrated for sub-8.33ms (120Hz ProMotion) frame times across iPhone 15 Pro and iPhone 16 Pro displays.
// Performance Metrics
Cold Launch:< 180 ms
Memory Footprint:~28 MB
Background Battery:0.0% / hr
Network Dependencies:0 (Offline-first)
Target Architecture:arm64 (Native)
Capacitor 6 · Supabase Realtime · CoreHaptics

Hybrid Native Bridge & Real-Time Tournament Sync

Bar Crawl Golf required instant synchronization across dozens of players moving through crowded downtown districts where cell signal fluctuates. We paired a custom Capacitor iOS native wrapper with Supabase WebSocket event broadcasting.

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Custom Native Haptics: iOS CoreHaptics integration triggers tactile click patterns on birdie putts, drink penalties, and hole transitions.
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Geofencing & GPS Verification: Validates that players have arrived within 75 yards of the designated bar before unlocking the hole scorecard.
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Optimistic Score Caching: Scorecard edits are committed to local IndexedDB first and synchronized upstream via WebSocket when connection restores.
// Real-Time Specs
Sync Latency:< 45 ms
GPS Radius Tolerance:± 25 meters
Concurrent Players:150+ / crawl
Database Security:Postgres RLS
App Store Rating:5.0 ★
Next.js 14 · Prisma ORM · Stripe Connect · Twilio 10DLC

White-Label Chapter Operating System

Fraternity operations require handling thousands of dollars in dues, managing hundreds of potential new members during rush, and broadcasting urgent safety alerts without violating federal telecom regulations.

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0% Markup Stripe Connect: Chapters connect their own bank accounts via Stripe Custom Express. Greekstack charges $0 per-transaction markup, saving chapters thousands in processing fees compared to legacy providers.
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TCPA & 10DLC Compliant SMS: Carrier-registered campaign pipelines ensuring urgent event announcements and rush invitations never get blocked by AT&T or Verizon spam filters.
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Digital Rush QR Pipeline: Prospective members scan a chapter QR code to check in at rush events, populating a real-time voting Kanban board for active brothers.
// Enterprise Architecture
Tenant Isolation:Postgres Schema Partitioning
Payment Gateway:Stripe Connect Custom
SMS Deliverability:99.4% (10DLC)
Dues Fee Markup:0.0%
Onboarding Portal:greekstack.app/onboard
Live Interactive Simulator · Bar Crawl Golf

Simulate a Bar Hole Scorecard.

Test how the scoring engine works in Bar Crawl Golf. Select your beverage and drink pace for Hole 1 to see the calculated golf score and crew leaderboard standing.

Select Hole 1 Beverage & Event
HOLE 1: THE SALTY ROOST PAR 3
Beverage Action: PBR Tallboy in Under 2 Min
Calculated Score: -2 (Eagle)
Leaderboard Position: T-1st of 24 Players
BFS Development LLC · iOS Engineering Desk

Ready to ship a native iOS product to the App Store?

From initial Swift architecture and TestFlight builds to App Store submission and real-time backend sync, Benjamin Sachwitz builds mobile experiences that respect user attention and hardware limits.

View Production Web Systems →