/onboarding

Swift / iOS — SDK detail

• Official docs: iOS SDK reference · Set up iOS SDK (onboarding)
• API reference: iOS SDK API docs
• Recipe (detect / install): SDK Recipes (Swift / iOS)

Why this differs from the home onboarding page: Set up iOS SDK uses a "YOUR_MOBILE_KEY" literal and a linear script. This skill keeps the same LDConfig / LDContextBuilder / LDClient.start…startWaitSeconds flow as Initialize the client, but resolves the mobile key from Xcode scheme env or Info.plist so archives are not missing the key. Substituting LDConfig(mobileKey: "YOUR_MOBILE_KEY", …) matches the docs verbatim when you only need a quick local paste.

Install the SDK: LaunchDarkly documents Swift Package Manager, CocoaPods, and Carthage (Install the SDK). Pin versions from the SDK releases page; the examples below follow the onboarding install style.

Swift Package Manager (Package.swift excerpt):

// ...
dependencies: [
    .package(url: "https://github.com/launchdarkly/ios-client-sdk.git", .upToNextMajor("9.15.0")),
    // Optional observability — iOS SDK v9.14+; see reference Install the SDK
    // .package(url: "https://github.com/launchdarkly/swift-launchdarkly-observability.git", .upToNextMajor("1.0.0")),
],
targets: [
    .target(
        name: "YOUR_TARGET",
        dependencies: ["LaunchDarkly"]
    ),
]
// ...

CocoaPods (Podfile):

use_frameworks!
target 'YourTargetName' do
  pod 'LaunchDarkly', '~> 9.15'
  # Optional — LaunchDarklyObservability, iOS SDK v9.14+
  # pod 'LaunchDarklyObservability', '~> 1.0'
end

Carthage (Cartfile):

github "launchdarkly/ios-client-sdk" ~> 9.15

Import (Import the SDK):

import LaunchDarkly
// Optional observability — iOS SDK v9.14+
// import LaunchDarklyObservability

Mobile key: Never ship a real key in source. ProcessInfo.processInfo.environment is set from the Xcode scheme for local runs; TestFlight / App Store builds need Info.plist (e.g. LaunchDarklyMobileKey) or xcconfig. Logical name: Apply: environment configuration.

Includes: Call configureLaunchDarkly() from application(_:didFinishLaunchingWithOptions:) (UIKit) or your SwiftUI startup path.

import LaunchDarkly

func configureLaunchDarkly() {
    let mobileKey: String?
    if let v = ProcessInfo.processInfo.environment["LAUNCHDARKLY_MOBILE_KEY"], !v.isEmpty {
        mobileKey = v
    } else if let v = Bundle.main.object(forInfoDictionaryKey: "LaunchDarklyMobileKey") as? String, !v.isEmpty {
        mobileKey = v
    } else {
        mobileKey = nil
    }

    guard let mobileKey else {
        print("LaunchDarkly: missing mobile key (scheme LAUNCHDARKLY_MOBILE_KEY for Xcode runs, or Info.plist LaunchDarklyMobileKey for archives).")
        return
    }

    let config = LDConfig(mobileKey: mobileKey, autoEnvAttributes: .enabled)
    // Optional observability — iOS SDK v9.14+; add package/pod and set config.plugins per
    // https://launchdarkly.com/docs/sdk/client-side/ios#initialize-the-client

    let contextBuilder = LDContextBuilder(key: "EXAMPLE_CONTEXT_KEY")
    guard case .success(let context) = contextBuilder.build() else {
        print("LaunchDarkly: could not build context")
        return
    }

    LDClient.start(config: config, context: context, startWaitSeconds: 5) { timedOut in
        if timedOut {
            print("SDK didn't initialize in 5 seconds. SDK is still running and trying to get latest flags.")
        } else {
            print("SDK successfully initialized with the latest flags")
            if let client = LDClient.get() {
                // For onboarding only — events are flushed automatically in normal use.
                client.flush()
            }
        }
    }

    print("SDK started.")
}