How to Build a Morse Code App in SwiftUI

A Morse Code app lets users translate plain text into dot-dash sequences and hear them played back in real time — perfect for students, radio enthusiasts, and anyone curious about this classic communication system.

iOS 17+ · Xcode 16+ · SwiftUI Complexity: Beginner Updated: 2026-05-12

Prerequisites

Xcode 16 or later installed on a Mac running macOS Sequoia+
Basic familiarity with Swift structs, @State, and SwiftUI views
An Apple Developer account (free tier is fine for Simulator testing)

Step-by-Step Build

1. Define the Data Model

Use a SwiftData @Model class to persist each translation so users can review their history later.

import SwiftData
import Foundation

@Model
final class MorseEntry {
    var id: UUID
    var inputText: String
    var morseCode: String
    var createdAt: Date

    init(inputText: String, morseCode: String) {
        self.id = UUID()
        self.inputText = inputText
        self.morseCode = morseCode
        self.createdAt = Date()
    }
}

2. Build the Translator UI

Create a SwiftUI view with a text field that converts input to Morse code live as the user types.

import SwiftUI

struct TranslatorView: View {
    @State private var inputText = ""
    @State private var morseOutput = ""

    var body: some View {
        VStack(alignment: .leading, spacing: 16) {
            TextField("Type text here…", text: $inputText)
                .textFieldStyle(.roundedBorder)
                .onChange(of: inputText) { _, newValue in
                    morseOutput = MorseEncoder.encode(newValue)
                }
            Text(morseOutput.isEmpty ? "— — · —" : morseOutput)
                .font(.system(.body, design: .monospaced))
                .foregroundStyle(morseOutput.isEmpty ? .secondary : .primary)
                .padding()
                .frame(maxWidth: .infinity, alignment: .leading)
                .background(Color(.secondarySystemBackground))
                .cornerRadius(10)
        }
        .padding()
        .navigationTitle("Translator")
    }
}

3. Learn and Translate with AVFoundation Audio

Wire up AVFoundation to generate a sine-wave tone so users can hear each dot and dash played at the correct timing ratio.

import AVFoundation

@Observable
final class MorsePlayer {
    private let engine = AVAudioEngine()
    private let node = AVAudioPlayerNode()
    private let dotDuration = 0.12

    func play(morse: String) {
        Task {
            for char in morse {
                switch char {
                case ".": await tone(duration: dotDuration)
                case "-": await tone(duration: dotDuration * 3)
                case " ": try? await Task.sleep(for: .seconds(dotDuration))
                default: break
                }
                try? await Task.sleep(for: .seconds(dotDuration))
            }
        }
    }

    private func tone(duration: Double) async {
        // Render a 700 Hz sine buffer via AVAudioEngine and schedule on node
    }
}

Common Pitfalls

Silent audio on device: Always call try AVAudioSession.sharedInstance().setActive(true) before starting your AVAudioEngine, or playback will silently fail on physical hardware.
Blocking the main thread: Generate PCM sample buffers on a background Task — computing long sequences on the main actor will freeze your UI mid-translation.
Encoding edge cases: Numbers, punctuation, and non-ASCII characters each need their own lookup entries; a missing key will crash a force-unwrap. Use optional chaining or a safe default.

Monetization: One-Time Purchase

A one-time purchase model suits a Morse Code app perfectly — users pay once and own the full feature set forever with no subscription fatigue. Implement it via StoreKit 2's Product.purchase() API: gate advanced features (custom WPM speed, alphabet quiz mode, history export) behind a .nonConsumable in-app purchase, then use Transaction.currentEntitlements to unlock them on every launch without a server.

Ship Faster with Soarias

Soarias scaffolds your entire SwiftUI project — @Model classes, StoreKit paywall, App Store screenshots, and fastlane lanes — in minutes from a single prompt inside Claude Code. For a beginner app like this, that eliminates roughly a day of boilerplate wiring and lets you focus entirely on perfecting the dot-dash audio engine and learning quiz flow.

FAQ

Do I need an Apple Developer account to build this?

No — you can build and run the app on the iOS Simulator with a free Apple ID. You only need a paid Apple Developer account ($99/year) when you're ready to install on a physical device via TestFlight or submit to the App Store.

How do I submit my Morse Code app to the App Store?

Archive your app in Xcode (Product → Archive), then upload via the Organizer window to App Store Connect. Complete your metadata, screenshots, and privacy nutrition labels, set your one-time purchase price, and click Submit for Review. Apple typically reviews beginner utility apps within 24–48 hours.

Last reviewed: 2026-05-12 by the Soarias team.