Added "Integration with Mobile Application" documentation

- added markdown file `docs/integration-with-mobile-application.md`
- added images
- added new section "Integration with Mobile Application" in the README

Author: tg666

README.md

@@ -23,6 +23,7 @@ An extended integration of [orestbida/cookieconsent](https://github.com/orestbid
 * [Triggering tags based on the consent](#triggering-tags-based-on-the-consent)
 * [Accessing the wrapper in the JavaScript](#accessing-the-wrapper-in-the-javascript)
 * [Integration with CMP application](#integration-with-cmp-application)
+* [Integration with Mobile Application](#integration-with-mobile-application)
 * [How the GTM integration works](#how-the-gtm-integration-works)
 * [How to update already published container](#how-to-update-already-published-containers)
   * [Migration from v0.4 to v0.5](#migration-from-v04-to-v05)
@@ -192,10 +193,10 @@ You can define a message that will be displayed in the consent modal's descripti
 
 ### Page scripts
 
-| Field               | Description                                                          |
-|---------------------|----------------------------------------------------------------------|
-| Manage page scripts | Enable if you want to easily manage existing `<script>` tags.        |
-| Script selector     | The name of a data attribute that is used for managed <script> tags. |
+| Field               | Description                                                            |
+|---------------------|------------------------------------------------------------------------|
+| Manage page scripts | Enable if you want to easily manage existing `<script>` tags.          |
+| Script selector     | The name of a data attribute that is used for managed `<script>` tags. |
 
 Managing page scripts is disabled by default. When the feature is enabled then the following notation can be used for scripts you want to manage:
 
@@ -399,6 +400,12 @@ Below this field you can define which columns the cookie table should contain.
 
 <img src="docs/images/widget-with-cookie-tables.png" alt="Widget with cookie tables" width="600">
 
+## Integration with Mobile Application
+
+Integration with the mobile application is described in a separate document:
+
+[Integration with Mobile Application](docs/integration-with-mobile-application.md).
+
 ## How the GTM integration works
 
 #### Consent initialization

docs/images/integration-with-mobile-application/cmp-settings-environments.png

@@ -0,0 +1,218 @@
+<div align="center" style="text-align: center; margin-bottom: 50px">
+<img src="images/logo.svg" alt="Cookie Consent Logo" align="center" width="250">
+<h1 align="center">Integration with Mobile Application</h1>
+</div>
+
+This document describes the concept of integrating with a mobile application using a [WebView](https://github.com/react-native-webview/react-native-webview) component in **React Native**.
+
+* [Prerequisites](#prerequisites)
+* [Mobile Application Detection](#mobile-application-detection)
+* [GTM Trigger Setup](#gtm-trigger-setup)
+* [GTM Tag Setup](#gtm-tag-setup)
+* [How It Works](#how-it-works)
+* [Integration with Consent Management Platform](#integration-with-consent-management-platform)
+
+## Prerequisites
+
+- **Cookie Consent** integrated via GTM
+- A dedicated URL available on the website (e.g. `/mobile-app-cookies`) that renders no content. This page is used to display the cookie banner within the mobile application.
+
+## Mobile Application Detection
+
+Detection of the mobile app is necessary in order to determine whether the website is being rendered in a regular browser or within a WebView.
+This can be achieved by setting a custom `User-Agent` header from the mobile app, for example: `MyApp/1.0.0`.
+
+In GTM, create a variable named `navigator.userAgent` of type **JavaScript Variable** with the value `navigator.userAgent`.
+
+<img src="images/integration-with-mobile-application/gtm-variable-user-agent.png" alt="GTM Variable navigator.userAgent" width="600">
+
+## GTM Trigger Setup
+
+Two triggers must be defined for proper functionality.
+
+The first trigger named `cookieConsent.mobileApp.webview` should be of type **Page View - DOM Ready** with the following conditions:
+
+1. `{{navigator.userAgent}}` contains `MyApp`
+2. `{{Page Path}}` does not equal `/mobile-app-cookies`
+
+This trigger runs only within the mobile app context and on all URLs except `/mobile-app-cookies`.
+
+<img src="images/integration-with-mobile-application/gtm-trigger-cookieConsent-mobileApp-webview.png" alt="GTM Trigger cookieConsent.mobileApp.webview" width="600">
+
+The second trigger named `cookieConsent.mobileApp.settings` should also be of type **Page View - DOM Ready** with the following conditions:
+
+1. `{{navigator.userAgent}}` contains `MyApp`
+2. `{{Page Path}}` equals `/mobile-app-cookies`
+
+This trigger runs only within the mobile app context and exclusively on the `/mobile-app-cookies` URL.
+
+<img src="images/integration-with-mobile-application/gtm-trigger-cookieConsent-mobileApp-settings.png" alt="GTM Trigger cookieConsent.mobileApp.settings" width="600">
+
+## GTM Tag Setup
+
+Corresponding to the triggers, two GTM tags are required.
+
+The first tag of type "Custom HTML", named `Cookie Consent - Mobile App WebView`, is triggered by `cookieConsent.mobileApp.webview`.
+
+This tag performs the following actions:
+
+- Hides the cookie banner entirely using a `<style>` block so it does not appear within the WebView.
+- If no valid consent is detected, a `postMessage` is sent to notify the app.
+
+<details>
+<summary>Click to view the code</summary>
+
+```html
+<script>
+    window.cookieConsentWrapperEvents = window.cookieConsentWrapperEvents || [];
+
+    window.cookieConsentWrapperEvents.push(['init', function () {
+        var plugin = window.CookieConsentWrapper.unwrap();
+
+        if (!plugin.validConsent() && 'ReactNativeWebView' in window) {
+            window.ReactNativeWebView.postMessage(JSON.stringify({
+                consent: null,
+                source: null,
+            }));
+        }
+    }]);
+</script>
+
+<style>
+    #cc--main {
+        display: none !important;
+    }
+</style>
+```
+</details>
+
+<img src="images/integration-with-mobile-application/gtm-tag-webview.png" alt="GTM Tag Cookie Consent - Mobile App WebView" width="600">
+
+The second tag of type "Custom HTML", named `Cookie Consent - Mobile App Settings`, is triggered by `cookieConsent.mobileApp.settings`.
+
+This tag performs the following actions:
+
+1. Hides the consent modal and close button of the settings modal using a `<style>` block.
+2. Immediately opens the settings modal and prevents it from being closed.
+3. Once the user interacts (clicks a button), consent is sent to the app using `postMessage`.
+
+<details>
+<summary>Click to view the code</summary>
+
+```html
+<script>
+    window.cookieConsentWrapperEvents = window.cookieConsentWrapperEvents || [];
+
+    window.cookieConsentWrapperEvents.push(['init', function () {
+        var plugin = CookieConsentWrapper.unwrap();
+
+        plugin.hideSettings = function () {};
+
+        plugin.showSettings(0);
+
+        document.querySelectorAll('#s-bns .c-bn, #c-bns .c-bn').forEach(function (button) {
+            button.addEventListener('click', function () {
+                setTimeout(function () {
+                    var consent = CookieConsentWrapper.consentCookieData;
+
+                    if (null === consent) {
+                        return;
+                    }
+
+                    var queryParameters = new URLSearchParams(window.location.search);
+                    var message = {
+                        consent: consent,
+                        source: queryParameters.get('source') || 'default',
+                    };
+
+                    if ('ReactNativeWebView' in window) {
+                        window.ReactNativeWebView.postMessage(JSON.stringify(message));
+                    }
+                }, 0);
+            });
+        });
+    }]);
+</script>
+
+<style>
+    #cc_div #cm, #s-c-bn {
+        display: none !important;
+    }
+
+    /* Possibly other styles to customize the look ... */
+</style>
+```
+</details>
+
+<img src="images/integration-with-mobile-application/gtm-tag-settings.png" alt="GTM Tag Cookie Consent - Mobile App Settings" width="600">
+
+## How It Works
+
+The mobile application must listen for incoming messages sent via `postMessage` from the GTM tags inside the WebView.
+Each message follows this format:
+
+```json5
+{
+"source": "default", // string or null
+"consent": {} // object representing the full user consent, equivalent to what is stored in cookies
+}
+```
+
+When a message is received with a `null` value in the `consent` field, the app should open the WebView with the URL `/mobile-app-cookies` and prompt the user for consent.
+
+When a message with a populated `consent` object is received, the app should hide the WebView and persist the consent.
+
+The mobile app must also ensure that a cookie (default name `cc-settings`) containing the user's consent is always available (if the consent has been stored) in the WebView context, so the banner reflects the current consent state.
+
+```mermaid
+sequenceDiagram
+    participant App as Mobile App
+    participant WebView as WebView (/)
+    participant GTM_WV as GTM Tag: Cookie Consent - Mobile App WebView
+    participant SettingsView as WebView (/mobile-app-cookies)
+    participant GTM_Set as GTM Tag: Cookie Consent - Mobile App Settings
+
+    App->>WebView: Load WebView with default URL (not /mobile-app-cookies)
+    WebView->>GTM_WV: DOM Ready → Trigger WebView tag
+    alt No valid consent
+        GTM_WV-->>App: postMessage({ consent: null, source: null })
+        App->>SettingsView: Load WebView with /mobile-app-cookies
+        SettingsView->>GTM_Set: DOM Ready → Trigger Settings tag
+        GTM_Set->>SettingsView: Show settings modal, wait for user action
+        SettingsView-->>App: postMessage({ consent: {...}, source: "default" })
+        App->>SettingsView: Hide WebView
+        App->>App: Store consent
+    else Valid consent
+        GTM_WV-->>App: No action needed (consent valid)
+    end
+
+    App->>WebView: Ensure "cc-settings" cookie is available (if stored)
+```
+
+## Integration with Consent Management Platform
+
+When integrating with the [Consent Management Platform (CMP)](https://github.com/68publishers/consent-management-platform), it is recommended to distinguish cookie definitions using separate environments.
+This is especially useful because the set of cookies used in a mobile application may differ from those on the website.
+Doing so ensures that the appropriate cookies are shown in the cookie table within the settings modal for each environment.
+
+<img src="images/integration-with-mobile-application/cmp-settings-environments.png" alt="CMP Settings - Environments" width="600">
+
+It is also advisable to distinguish environments when storing user consents, so the CMP dashboard clearly shows whether consent originated from the website or the mobile application.
+
+To achieve this, a GTM variable named `cmp.environment` of type **Custom JavaScript** can be created:
+
+<details>
+<summary>Click to view the code</summary>
+
+```javascript
+function () {
+    return {{navigator.userAgent}}.includes('MyApp') ? 'mobile' : 'default';
+}
+```
+</details>
+
+<img src="images/integration-with-mobile-application/gtm-variable-cmp-environment.png" alt="GTM Variable - cmp.environment" width="600">
+
+This variable should then be used in the field **Integration > CMP API > Environment code**:
+
+<img src="images/integration-with-mobile-application/gtm-cmp-environment-settings.png" alt="GTM Tag - CMP Environment settings" width="300">