branch.io implementation seems quite complex as described and they don't publish their prices on their site...

Until Flutterflow will come up with an alternative solution for Firebase dynamic links sharing, I'm using a custom action for sharing (a post in my case).

Important: you need to publish your app to the web as it relies on a web url like https://your_domain/post/f3wHXd9pJmoT3P3pj

You can adjust and use it to your use case.

It supports web and mobile. On the web it tries to use the browser share functionality available in modern browsers (See a browser sharing example: https://codepen.io/stoumann/pen/eYBQbPj) with fallback to sending an email.

On the mobile it shares using share_plus.dart package like flutterflow.

Hope it helps someone 🙂

// Automatic FlutterFlow imports\nimport '/backend/backend.dart';\nimport '/backend/schema/structs/index.dart';\nimport '/backend/schema/enums/enums.dart';\nimport '/backend/supabase/supabase.dart';\nimport '/actions/actions.dart' as action_blocks;\nimport '/flutter_flow/flutter_flow_theme.dart';\nimport '/flutter_flow/flutter_flow_util.dart';\nimport '/custom_code/actions/index.dart'; // Imports other custom actions\nimport '/flutter_flow/custom_functions.dart'; // Imports custom functions\nimport 'package:flutter/material.dart';\n// Begin custom action code\n// DO NOT REMOVE OR MODIFY THE CODE ABOVE!\n\nimport 'package:share_plus/share_plus.dart';\nimport 'package:url_launcher/url_launcher.dart';\nimport 'package:universal_html/html.dart' as html;\nimport 'package:flutter/foundation.dart' show kIsWeb;\n\nFuture sharePost(String postId) async {\n  final shareText =\n\t\"Hey!%20%F0%9F%91%8B%0A%0AI%20just%20discovered%20<YOUR_APP>%20-%20it%27s%20a%20<YOUR DESCRIPTION>%0A%0ACheck%20it%20out%3A%20https%3A%2F%2F<YOUR_DOMAIN>%2Fpost%2F$postId%0A%0ASee%20you%20there%20%F0%9F%98%8A%0A%0A\";\n  final emailSubject = \"Found%20this%20cool%20new%20app\";\n\n  if (kIsWeb) {\n    try {\n      // Try to use the Web Share API\n      try {\n        final shareData = {\n          'title': Uri.decodeFull(emailSubject),\n          'text': Uri.decodeFull(shareText),\n          'url': 'https://<YOUR_DOMAIN>/post/$postId'\n        };\n\n        await html.window.navigator.share(shareData);\n        return;\n      } catch (webShareError) {\n        // Web Share API not available or failed, fall back to email\n        final emailUrl = 'mailto:?subject=$emailSubject&body=$shareText';\n        final uri = Uri.parse(emailUrl);\n        if (await canLaunchUrl(uri)) {\n          await launchUrl(uri);\n        } else {\n          throw 'Could not launch email client';\n        }\n      }\n    } catch (e) {\n      print('Error sharing content: $e');\n      // You might want to show a snackbar or dialog here to inform the user\n    }\n  } else {\n    // Mobile platforms using share_plus\n    try {\n      await Share.share(\n        Uri.decodeFull(shareText),\n        subject: Uri.decodeFull(emailSubject),\n      );\n    } catch (e) {\n      print('Error sharing content: $e');\n      // You might want to show a snackbar or dialog here to inform the user\n    }\n  }\n}

Replace <YOUR_APP>, <YOUR_DOMAIN> and <YOUR_DESCRIPTION>

Also add in PubSpec Dependencies:
universal_html: ^2.2.4
share_plus: 10.1.3
share_plus_platform_interface: ^5.0.2

Dynamic links