Why build natively for iOS
Cross-platform frameworks are a sensible default for many products, and we build with them too. Native iOS is the stronger choice when the app leans on Apple-specific capabilities, when it has to feel indistinguishable from a first-party app, or when your users are concentrated on iPhone and you'd rather do one platform very well than two adequately.
- Day-one access to new APIs. New frameworks and OS features arrive in Swift first; wrappers for other stacks follow later, if at all.
- Deep system integration. Widgets, Live Activities, Siri and App Intents, Share extensions and watchOS companions are all native targets.
- Predictable performance. No bridge or rendering engine between your code and the system, which matters for camera, audio, AR and heavy lists.
- Smaller surface for upgrade risk. You depend on Apple's toolchain and a handful of libraries instead of a framework plus its plugin ecosystem.
If you're still deciding between platforms, our overview of how we run offshore mobile projects end to end compares native and shared-code options side by side.
Swift, SwiftUI and UIKit: how we structure an iOS codebase
New projects start in Swift with SwiftUI for most screens. SwiftUI's declarative model makes state easier to reason about and previews speed up design iteration. UIKit still earns its place for a few things, such as highly customized collection layouts, some text-editing behavior and mature third-party components, and the two interoperate cleanly through UIHostingController and UIViewRepresentable.
Modular packages
Features split into Swift Package Manager modules so build times stay reasonable and teams can work in parallel without merge pain.
Swift concurrency
async/await and actors for networking and shared state, with strict concurrency checking turned on so data races are caught at compile time.
Testable architecture
View logic kept out of views, dependencies injected, and networking behind protocols so unit tests don't need a live server.
Design system in code
Typography, color and spacing tokens defined once, with Dynamic Type and Dark Mode supported from the first screen.
We pick the minimum supported iOS version with you during discovery. Supporting older versions widens your audience but limits which SwiftUI APIs we can use without fallbacks, so it's a product decision as much as a technical one.
Building across the Apple ecosystem
An iPhone app is often the start, not the whole product. These are the extensions and frameworks clients ask us for most, and what each involves.
| Capability | What it's for | What to plan for |
|---|---|---|
| WidgetKit widgets | Glanceable content on the Home Screen, Lock Screen and StandBy. | Widgets render from timelines, not live code, so data refresh needs careful design. |
| watchOS apps | Quick actions, notifications and health or fitness tracking on the wrist. | Separate UI, tight battery limits and syncing with the phone app. |
| App Clips | A small, instant slice of your app launched from a link, QR or NFC tag. | Strict size limits and a focused flow; shared code must be carved out deliberately. |
| HealthKit | Reading and writing health and fitness data with the user's permission. | Granular permissions, clear usage strings and extra App Review scrutiny. |
| StoreKit 2 | In-app purchases and subscriptions with a modern Swift API. | Server-side receipt and subscription status handling, plus testing in sandbox and StoreKit config files. |
Health data deserves particular care. For clinical or patient-facing products, our healthcare app delivery approach covers how we design data flows so you can meet HIPAA and similar obligations alongside your counsel.
Privacy manifests and App Tracking Transparency
Apple's privacy rules are now a build requirement, not just a policy page. We treat them as part of the definition of done for every release.
- Privacy manifests. Apps and many third-party SDKs must ship a PrivacyInfo.xcprivacy file declaring the data they collect and the reasons they use certain sensitive APIs. We audit every dependency for its own manifest and flag SDKs that don't provide one.
- App Tracking Transparency. If the app tracks users across other companies' apps or websites, it must ask permission through the ATT prompt first. We help you decide whether you actually need tracking, and if so, when to ask so the prompt makes sense to users.
- Privacy nutrition labels. The App Store privacy section has to match what the app and its SDKs really do. We produce a data inventory you can use to fill it in accurately.
- Permission strings. Camera, location, contacts and health access each need a clear purpose string. Vague ones are a common reason for rejection.
TestFlight and App Store review
Every sprint ends with a TestFlight build. Internal testers on your App Store Connect team get builds immediately; external testers need a short beta review before the first build of a version reaches them. TestFlight builds expire after 90 days, so we keep a current one available for stakeholders at all times.
- 1
Pre-submission checklist
Demo account credentials for reviewers, notes explaining non-obvious features, correct age rating and export compliance answers.
- 2
Guideline review
We check flows against the App Review Guidelines that most often cause trouble: sign-in options, account deletion, payments for digital goods and user-generated content moderation.
- 3
Submission and response
If a reviewer raises an issue, we reply through Resolution Center with specifics, or fix and resubmit the same day where possible.
- 4
Phased release
Automatic updates roll out gradually over several days, so a regression can be paused before it reaches everyone.
Migrating from UIKit to SwiftUI
A full rewrite is rarely the right answer for an existing UIKit app. We migrate incrementally, so the app keeps shipping while the codebase modernizes.
- 1
Assess
Map screens by change frequency and complexity. Screens your team touches every sprint are the best early candidates.
- 2
Build shared foundations
Introduce design tokens, navigation coordination and a state layer that both UIKit and SwiftUI screens can use.
- 3
Migrate screen by screen
New features ship in SwiftUI hosted inside the existing navigation; old screens move over when they next need meaningful work.
- 4
Retire legacy code
Once a flow is fully SwiftUI, remove the old controllers and their tests rather than leaving dead code behind.
For older Objective-C apps or codebases with years of accumulated shortcuts, our app modernization service covers the wider refactoring plan.
Testing on a real device matrix
Simulators are fast and fine for most UI work, but they don't reproduce real camera behavior, thermal throttling, push notification delivery or memory pressure on older hardware. We test on physical devices for every release candidate.
| Dimension | What we cover |
|---|---|
| Screen sizes | Smallest supported iPhone, a current standard model, the largest Pro Max class, and iPad if supported. |
| OS versions | Your minimum supported iOS version and the current release, plus the public beta ahead of each autumn launch. |
| Accessibility | VoiceOver navigation, largest Dynamic Type sizes, Reduce Motion and contrast settings. |
| Conditions | Poor network, airplane mode, low storage, background and foreground transitions. |
Automated coverage uses XCTest for unit tests and XCUITest for critical journeys, running in CI on every pull request. Once you're live, ongoing maintenance and support keeps the app current through each annual iOS release.