App Review rejections
Guideline violations block launch and eat release cycles. We pre-screen against App Review guidelines at design stage and manage rejection responses with Apple's review team.
SwiftUI StoreKit 2 App Store WCAG
Swift iOS Development Services for Native iPhone and iPad Apps
Twenty-seven shipped iOS apps live on the App Store for US and EU users — JoyJet's social video feed, LiMP's WireGuard VPN with NetworkExtension, Signatory Pro's e-signature client with biometric auth. SwiftUI-fluent, accessibility-trained, App Store submission included in every engagement.
We deliver Swift iOS engineering for consumer apps, regulated enterprise clients and cross-platform platforms — SwiftUI-first where iOS 16+ is the floor, UIKit where fine-grained control or legacy SDK integration requires it. Every engagement includes TestFlight distribution, App Store submission, App Review management and post-launch crash monitoring. From zero-log VPNs with NetworkExtension to HealthKit-integrated clinical apps, we have shipped in the categories that require the most careful entitlement, privacy manifest and App Review handling.
Challenges
Industry challenges we solve
SwiftUI and UIKit interop
Mixing paradigms creates view lifecycle conflicts and layout glitches. We establish clear boundaries and use UIViewRepresentable/UIViewControllerRepresentable patterns explicitly.
Background task scheduling
iOS aggressively kills background tasks. We use BackgroundTasks, Background App Refresh and silent push to maintain data freshness within OS constraints.
Keychain and biometric auth edge cases
Face ID lockout, device-without-passcode and accessibility accommodations surface in the wild. We test the full error matrix and implement graceful fallbacks.
StoreKit receipt validation
Client-side receipt validation is insufficient for regulated and subscription products. We implement server-side App Store Server API validation with renewal and refund webhooks.
Privacy manifest compliance
Xcode 15+ requires PrivacyInfo.xcprivacy declarations for all API usage and third-party SDKs. We audit and declare every required reason before submission.
Solutions
Solutions we build
Consumer apps
Social, entertainment and productivity apps on the App Store — SwiftUI, push, iCloud sync, StoreKit subscriptions.
FinTech and wallet apps
Open Banking integrations, biometric auth, Secure Enclave key storage and PCI DSS-aware card display.
HealthKit clinical apps
HIPAA-capable health data ingestion, HealthKit read/write, DICOM viewer integration, clinical workflow UIs.
VPN and NetworkExtension
WireGuard, OpenVPN and custom protocol tunnels with on-demand rules, split tunneling and zero-log architecture.
Enterprise and B2B apps
Internal tooling, MDM-distributed apps with Managed App Config, and SSO via ASWebAuthenticationSession.
App modernisation
Objective-C to Swift migrations, UIKit to SwiftUI incremental rewrites and legacy SDK replacement.
Stack
Technology stack
Swift 5.10, SwiftUI, UIKit, Combine, async/await, StoreKit 2, NetworkExtension, CoreData, CoreLocation, HealthKit, LocalAuthentication, Alamofire, Firebase, Sentry.
Compliance
Compliance & regulations
GDPR-aligned · HIPAA-capable · WCAG 2.2 · CCPA-acknowledged
EU
- GDPR — App Tracking Transparency, data subject rights.
- eIDAS — identity verification flows.
- EAA — accessibility compliance for EU market apps.
- DSA — transparency requirements for digital services.
US
- HIPAA — HealthKit data handling and clinical data flows.
- CCPA/CPRA — ATT + consent and opt-out flows.
- COPPA — age-gating and children's privacy.
- Section 508 / WCAG 2.2 — VoiceOver, Dynamic Type.
Shared: App Store privacy manifest (PrivacyInfo.xcprivacy), OWASP Mobile Top 10, SBOM for third-party SDKs.
Cases
Selected Swift iOS case studies
Social Media · Consumer Tech
JoyJet
Production social platform — App Store + Google Play, live across the US and EU — with geo Radar, encrypted messaging and a virtual economy.
Consumer Privacy · Mobile
LiMP
Consumer WireGuard VPN app for iOS and Android with zero-log architecture, launched across the US and EU.
LegalTech · Mobile · CRM
Signatory Pro
Native iOS and Android e-signature clients with a Symfony + React CRM for a cross-border law firm — KYC onboarding and a defensible evidence trail for US & EU matters.
Why YuSMP
Why iOS teams choose YuSMP
27 shipped App Store apps
From social platforms to regulated medical workstations — submission experience across every major App Review category, including health, finance and VPN.
NetworkExtension expertise
One of the few agencies with production WireGuard VPN experience — entitlements, on-demand rules, split tunneling and zero-log architecture.
SwiftUI and UIKit depth
Senior engineers who know when to mix paradigms, how to migrate incrementally, and what SwiftUI still cannot do cleanly in 2025.
FAQ
Swift iOS FAQ
SwiftUI or UIKit — which do you use?
SwiftUI for new projects targeting iOS 16+ — declarative layouts, live previews, and significantly less boilerplate. UIKit where we need fine-grained control, legacy codebase integration, or components SwiftUI does not yet expose cleanly. Most production apps mix both.
Do you handle App Store submission?
Yes. We manage provisioning profiles, entitlements, app review submissions, TestFlight beta distribution and rejection resolution. App Store submission is part of every iOS engagement, not an extra.
Can you implement in-app purchases and subscriptions with StoreKit 2?
Yes. We implement consumable, non-consumable and auto-renewable subscriptions with StoreKit 2's async/await API, handle receipt validation server-side, and implement upgrade, downgrade and restore flows.
How do you implement biometric authentication?
We use LocalAuthentication framework for Face ID and Touch ID, with a PIN fallback and proper Keychain storage for credentials. We test on devices, not simulators, and handle the full error matrix including lockout and fallback scenarios.
Can you build VPN or NetworkExtension apps?
Yes. LiMP is a production consumer VPN on WireGuard with NetworkExtension — zero-log architecture, split tunneling and on-demand rules. NetworkExtension requires a paid developer account and specific entitlements; we handle the provisioning setup.
How do you handle background tasks and push notifications?
We use BackgroundTasks framework for deferred work, Background App Refresh for lightweight updates, and APNs for push — with silent pushes for data sync and user-facing notifications with actionable categories.
What is your approach to privacy manifest compliance?
We audit all third-party SDKs for required reason declarations in PrivacyInfo.xcprivacy, map all API usage to approved reasons, and verify App Store Connect does not flag privacy issues before submission. Required since Xcode 15 for App Store.
Ship a native iOS app with senior Swift engineers
Response within 1 business day. NDA on request.