iOS · watchOS
Cairn — Hiking companion
Offline-first trail tracking with Live Activities, dynamic island progress, and a watch-only mode that survives a weekend without charging.
Native apps,
built for the Apple ecosystem.
karenlee is an independent studio designing and engineering native experiences for iPhone, iPad, Mac, Apple Watch, Apple TV and Apple Vision Pro — from product strategy through App Store launch.
Shipping for every Apple platform
What we do
End-to-end product work, with one team.
Strategy, product design, native engineering, and App Store delivery — handled by people who use these devices every day.
Product design
Human Interface Guidelines from the inside out — typography, motion, accessibility, and the polish that earns App Store editorial features.
Native engineering
Swift, SwiftUI, UIKit, AppKit, Metal, RealityKit, Combine, async/await. Apple-first, no cross-platform shortcuts.
App Store delivery
App Store Connect, TestFlight, App Review, privacy nutrition labels, certificates, provisioning, App Store Optimization.
System integrations
Sign in with Apple, HealthKit, HomeKit, CloudKit, WidgetKit, Live Activities, App Intents, ShazamKit, Core ML, ARKit, Vision.
Cross-device experiences
Universal apps, Handoff, Universal Clipboard, Continuity Camera, AirDrop and Shared with You — designed as one product.
Privacy & security
App Tracking Transparency, on-device intelligence, Secure Enclave, Keychain, end-to-end encryption — privacy as a feature.
Every Apple platform
Designed for the device in your hand — or on your face.
iOS & iPadOS
Consumer apps, B2B tools, Stage Manager-aware iPad experiences, Live Activities, Lock Screen widgets, App Clips.
macOS
Pro tools, menu-bar utilities, Catalyst migrations, native AppKit, SwiftUI desktop, sandboxing & notarization.
watchOS
Workouts, complications, smart stacks, Double Tap, Always On, HealthKit integrations and standalone watch apps.
tvOS
Living-room interfaces, Siri Remote interactions, focus engine, top shelf, video streaming and game controller support.
visionOS
Spatial computing on Apple Vision Pro — windowed, immersive and shared-space apps. RealityKit, ARKit, hand and eye input, and 3D content authored with Reality Composer Pro.
How we work
Six steps, no surprises.
Discovery
Goals, constraints, audience, success metrics. A scoping doc, not a sales deck.
Product design
HIG-aligned flows, prototypes you can run on-device, accessibility from day one.
Architecture
Swift Concurrency, modules, persistence, CloudKit or your backend — written down before code.
Build
Two-week iterations. TestFlight after every sprint, with notes a non-engineer can read.
Launch
App Review, marketing assets, privacy nutrition labels, screenshots, App Store Optimization.
Ongoing
Each fall: iOS / macOS / watchOS / tvOS / visionOS SDK adoption, before the public release.
48
Apps shipped on the App Store
12+
Years building for Apple platforms
6
Apple platforms supported
100%
Native Swift, no wrappers
Selected work
See all work
A few recent launches.
macOS
Stack — Engineering notebook
A markdown-native pro tool for software teams. Native AppKit, Spotlight indexing, full-disk Quick Look extensions.
visionOS
Atlas — Spatial workspace
Multi-window research surface for Vision Pro. Persistent volumes, hand-gesture pinning, and shared-space FaceTime sessions.
tvOS
Loft — Living-room photo frame
Ambient photo display sourced from iCloud Photos, with screensaver-style transitions and Siri Remote navigation.
Common questions
Things people ask before getting in touch.
Do you only build native, or will you use React Native / Flutter / web tech?
Native only. SwiftUI, UIKit, AppKit, RealityKit, Metal. We pick Apple's stack because it's how apps stay supported across a decade of OS releases without being rewritten.
How small is too small? Can a solo founder hire you?
We take on solo founders, post-Seed startups and enterprises. Most projects start at four weeks. If your idea is too early to scope, ask about our paid one-week discovery.
Do you own the source code we end up with?
You do — fully, on delivery. We publish to your App Store Connect account, transfer the repository, and provide certificates and provisioning under your Apple Developer team.
Do you handle App Review for us?
Yes. We prepare metadata, screenshots, privacy nutrition labels, App Tracking Transparency strings, and respond to App Review on your behalf when binaries come back rejected.
Where are you based?
Downingtown, Pennsylvania. We work remotely with clients across North America and Europe and align hours with US Eastern by default.