chore: getting started doc for iOS (#1652)

* getting started doc for iOS

* added more screenshots

---------

Co-authored-by: AR Abdul Azeez <abdul@onesignal.com>

Author: abdulraqeeb33

GettingStarted.md

@@ -0,0 +1,101 @@
+# Getting Started with the Red App
+
+The **Red App** is a SwiftUI sample application that exercises every major feature of the OneSignal iOS SDK. Use it to validate SDK behavior, test integrations, and explore the API surface on a simulator or physical device.
+
+<p align="center">
+  <img src="docs/assets/red-app-screenshot.png" alt="Red App screenshot" width="300"/>
+</p>
+
+## Prerequisites
+
+| Requirement | Minimum Version |
+|-------------|-----------------|
+| macOS       | 13 Ventura+     |
+| Xcode       | 15.0+           |
+| Swift       | 5.9+            |
+| iOS target  | 16.0+           |
+
+## Running the App
+
+### Option A — Open via the workspace (recommended)
+
+1. Open `iOS_SDK/OneSignalSDK.xcworkspace` in Xcode.
+2. In the scheme selector (top-left toolbar), choose **OneSignalSwiftUIExample**.
+3. Pick a simulator (e.g. iPhone 17 Pro) or a connected device.
+4. Press **Cmd + R** to build and run.
+
+Your Xcode toolbar should look like this — scheme set to **OneSignalSwiftUIExample**, a simulator chosen, and the app running:
+
+<p align="center">
+  <img src="docs/assets/xcode-run-button.png" alt="Xcode toolbar showing the app running" width="700"/>
+</p>
+
+The workspace contains multiple schemes. Make sure **OneSignalSwiftUIExample** is selected:
+
+<p align="center">
+  <img src="docs/assets/xcode-scheme-selector.png" alt="Xcode scheme selector showing OneSignalSwiftUIExample" width="700"/>
+</p>
+
+Once the app is running, SDK debug logs stream to the Xcode console — useful for verifying network calls, subscription state, and in-app message events:
+
+<p align="center">
+  <img src="docs/assets/xcode-console-output.png" alt="Xcode console showing SDK debug logs" width="700"/>
+</p>
+
+### Option B — Open from the terminal
+
+```bash
+open iOS_SDK/OneSignalSDK.xcworkspace
+```
+
+Then follow steps 2–4 from Option A.
+
+### Option C — Open only the example project
+
+> Use this if you only need the sample app and don't plan to modify the SDK source.
+
+```bash
+open iOS_SDK/OneSignalSwiftUIExample/OneSignalSwiftUIExample.xcodeproj
+```
+
+Select the **OneSignalSwiftUIExample** scheme, pick a destination, and run.
+
+> **Note:** Opening the `.xcworkspace` (Options A/B) is preferred because it links the sample app against the SDK source, so any local SDK changes are picked up automatically.
+
+## Using Your Own App ID
+
+The default App ID (`77e32082-ea27-...c72e141824ef`) is a shared test key. To use your own:
+
+1. Open `iOS_SDK/OneSignalSwiftUIExample/OneSignalSwiftUIExample/Services/OneSignalService.swift`.
+2. Replace the `defaultAppId` value with your OneSignal App ID (available at [onesignal.com](https://onesignal.com)).
+
+## Features
+
+The Red App is organized into scrollable sections, each mapping to a OneSignal SDK capability:
+
+| Section | What It Does |
+|---------|-------------|
+| **Logs** | Collapsible live SDK log viewer with a configurable entry limit and clear button. |
+| **App Info** | Displays the current App ID and a consent-required toggle that gates SDK data processing. |
+| **User** | Shows login status (Anonymous / Identified) and External ID. Login and logout buttons to switch between user states. |
+| **Push** | Displays the Push Subscription ID, an enable/disable toggle, and permission status. |
+| **Send Push Notification** | Quick-fire buttons (Simple, Custom) to send test push notifications to the current device. |
+| **In-App Messaging** | Pause/resume in-app messages. |
+| **Send In-App Message** | Trigger a test in-app message. |
+| **Aliases** | Add and remove key-value aliases for the current user. |
+| **Email** | Add and remove email subscriptions. |
+| **SMS** | Add and remove SMS subscriptions. |
+| **Tags** | Manage user tags used for audience segmentation. |
+| **Outcome Events** | Fire unique, regular, or valued outcome events for analytics. |
+| **Triggers** | Set and remove in-app message triggers. |
+| **Track Event** | Send custom user events with optional properties. |
+| **Location** | Toggle location sharing and request location permissions. |
+| **Live Activities** | Start and manage iOS Live Activities via OneSignal. |
+
+## Troubleshooting
+
+| Problem | Fix |
+|---------|-----|
+| Build fails with missing framework | Make sure you opened the **`.xcworkspace`**, not the `.xcodeproj`. |
+| Push notifications don't arrive on simulator | Push delivery requires a **physical device** with a valid APNs configuration. The simulator supports permission prompts and token generation but won't receive remote pushes. |
+| "Consent Required" blocks SDK calls | Toggle **Consent Required** off, or call the consent API to grant consent. |