IOS APP DEVELOPMENT
PROPELOO engineers native iOS applications in Swift — from architecture and SwiftUI through Core Data, push notifications, App Store submission and the performance optimisation that determines your App Store rating. Native iOS done right is invisible to users. Done wrong, it shows in every frame drop and every crash report.
iOS users have higher average revenue per user and higher expectations for app quality. An app that looks like a React Native wrapper on iOS — wrong gesture handling, non-native navigation transitions, missing haptic feedback, slow scroll performance — will be rated poorly and uninstalled. Native Swift with SwiftUI gives you full access to every iOS capability: Face ID via LocalAuthentication, HealthKit, ARKit, Core ML, Live Activities, Dynamic Island and every future Apple API on day one. PROPELOO builds iOS apps that feel native because they are native — leveraging the platform, not working around it.
Native iOS development requires platform-specific expertise at every layer.
Modern declarative SwiftUI with proper state management — @StateObject, @EnvironmentObject, NavigationStack, async/await for data fetching and matched geometry animations.
Instruments profiling for CPU/memory/energy, lazy loading in List/ScrollView, image caching with AsyncImage, background task management and battery optimisation.
Deep iOS integration — HealthKit for health data, ARKit for augmented reality, Core ML for on-device machine learning, Shortcuts, Widgets, Live Activities and Dynamic Island.
Keychain Services for secure storage, LocalAuthentication for biometrics, certificate pinning with URLSession, App Transport Security and data protection file attributes.
StoreKit 2 implementation for subscriptions, consumables and non-consumable purchases, receipt validation, subscription management UI and App Store promotional pricing.
Xcode Cloud or GitHub Actions with Fastlane, automated TestFlight distribution, App Store submission automation and certificate/provisioning profile management.
The best iOS apps are not cross-platform apps that run on iOS. They are apps designed specifically for the iPhone — for its gestures, its metaphors and its ecosystem.
SwiftUI is Apple's direction. New APIs (Live Activities, WidgetKit, App Intents) are SwiftUI-first. UIKit interoperability via UIViewRepresentable handles edge cases. Starting a new iOS app in UIKit in 2024 is building technical debt from day one.
Axiom:
Swift concurrency (async/await, actors, structured concurrency) eliminates the callback hell of completion handlers. Combine remains useful for reactive pipelines. New iOS apps should use async/await as the primary concurrency model.
Axiom:
App Store review takes 1-3 days for new apps and 1-2 days for updates. Rejections can add 1-2 weeks. App Review guideline compliance must be designed in — especially for apps with subscriptions, user-generated content or physical goods. Review violations discovered at submission are expensive to fix under deadline.
Axiom:
iOS users are privacy-conscious and App Store privacy labels are visible before download. Minimum permission requests, on-demand permission requests in context, clear privacy policy and App Tracking Transparency compliance are product requirements, not legal formalities.
Axiom:
Each choice has implications for maintainability, performance and App Store compliance.
Impact: SwiftUI for new apps targeting iOS 16+. UIKit for apps requiring very custom UI or maintaining existing UIKit codebases. Hybrid is the pragmatic production choice.
Impact: Native SwiftUI state for most apps. TCA for complex apps with many interconnected state machines where testability is critical.
Impact: SwiftData for new iOS 17+ apps. Core Data for apps targeting iOS 16 or earlier. Never UserDefaults for sensitive data.
Impact: URLSession with async/await is sufficient for most apps. Alamofire for teams that prefer its API. Apollo for GraphQL-heavy backends.
Impact: StoreKit 2 is the modern subscription API — async/await, better error handling, built-in subscription management. Always implement server-side receipt validation for subscription status.
Impact: FCM for apps that also have Android — single SDK, unified analytics. APNs direct for iOS-only apps where notification latency and control matter.
Social, lifestyle or utility app with SwiftUI, smooth animations, HealthKit/location integration and App Store optimised listing.
Banking or investment app with Face ID auth, Keychain token storage, biometric transaction confirmation and certificate pinning.
HealthKit integration, HIPAA-compliant data storage, telehealth video and ClinicalKit for clinical workflows.
ARKit augmented reality or Core ML on-device machine learning application leveraging Apple Silicon Neural Engine.
MDM-managed enterprise iOS app with SSO, offline capability, Core Data sync and Apple Business Manager distribution.
StoreKit 2 subscription implementation with free trial, paywall A/B testing, churn prevention flow and App Store Small Business Programme optimisation.
Stack: Swift 5.9+, SwiftUI, UIKit, Xcode 15, Swift Concurrency
Stack: SwiftData, Core Data, Realm, UserDefaults, Keychain
Stack: HealthKit, ARKit, Core ML, StoreKit 2, WidgetKit, App Intents
Stack: URLSession, Alamofire, Apollo GraphQL, Firebase
Stack: Xcode Cloud, Fastlane, GitHub Actions, TestFlight, App Store Connect API
Stack: XCTest, XCUITest, Quick/Nimble, Instruments, TestFlight
Auth tokens, passwords and sensitive data belong in Keychain Services — hardware-backed secure storage. Never UserDefaults or plaintext files.
LocalAuthentication with Secure Enclave — private keys never leave hardware. Face ID/Touch ID as second factor, not password replacement.
File protection attributes (.complete, .completeUnlessOpen) encrypt files at rest using device passcode key. Required for sensitive user data.
URLSession certificate pinning for financial and health apps. Prevents MITM on compromised networks.
ATS enforces HTTPS for all connections. Exceptions require justification in Info.plist and App Review scrutiny.
Request only needed permissions, in context, just before first use. NSPhotoLibraryUsageDescription, NSCameraUsageDescription etc must clearly explain the use.
App structure, navigation model, data layer, state management and platform API requirements.
Xcode project, SwiftUI architecture, CI/CD with TestFlight, signing configuration.
Feature development in 2-week sprints. Performance testing on physical devices throughout.
HealthKit, notifications, widgets, in-app purchases — platform APIs requiring specific review compliance.
Animation refinement, Instruments profiling, battery optimisation and accessibility audit.
XCTest unit tests, XCUITest UI automation, TestFlight beta with real users on physical devices.
App Store Connect metadata, screenshots, privacy labels, Review guideline compliance and submission.
SwiftUI for new apps targeting iOS 16+. It is Apple's preferred framework with the best tooling support (Xcode previews, SwiftData integration). UIKit for existing codebases or components requiring pixel-perfect custom rendering. Hybrid is common in production — SwiftUI screens, UIKit for complex custom components.
Simple utility app (10-15 screens): 8-12 weeks. Medium complexity consumer app (25-40 screens with backend): 12-20 weeks. Complex app (social, fintech, health with extensive platform APIs): 4-8 months. Apple review adds 1-5 days per submission.
Most rejections are for specific guideline violations — we document the most common (2.1 performance crashes, 4.0 copycat apps, 3.1.1 in-app purchase bypass) and design around them proactively. We include App Review notes for non-obvious features and test on the oldest supported device before submission.
Limited sharing is practical. Shared: REST API client logic, business rules in Kotlin Multiplatform Mobile (KMM). Not shared: UI (SwiftUI vs Jetpack Compose are fundamentally different), platform APIs (HealthKit vs Google Fit), navigation. We recommend native over cross-platform for any app where the native experience is a product differentiator.
Target iOS 16+ to reach 95%+ of active iPhones while accessing modern APIs. Use #available checks for iOS 17+ features with graceful fallbacks. Avoid iOS 15 if possible — SwiftData and other modern APIs are iOS 17+.
Apple takes 30% of in-app purchases and subscriptions. Drops to 15% for developers earning under $1M/year (Small Business Programme) and for subscriptions after 12 months of continuous subscription by a user. Physical goods and services are excluded — only digital content requires Apple's payment system.
StoreKit 2 is the modern API. Implement: subscription groups with free trial, upgrade/downgrade paths, StoreKit Transaction listener for purchases outside the app, server-side App Store Server Notifications for renewal events, and subscription status displayed clearly in app settings.
TestFlight is Apple's beta distribution platform — up to 10,000 external testers invited via email or public link, without App Store listing. Internal testing (up to 100 team members) requires no review. External testing requires basic review (1-2 days). We set up TestFlight as part of CI/CD so every main branch commit deploys to internal testers automatically.