What are the requirements for adding images or banners to push notifications?

To add an image or banner to your push notification, you need to provide a direct URL to the image file.

Here are the key requirements and best practices:

1. Public Accessibility: The image URL must be publicly accessible via a direct link. This means anyone with the link can view the image without needing to log in or authenticate.

2. Hosting:

   • The image needs to be hosted somewhere accessible via a URL.
   • If you are sending notifications to a large audience, it's crucial to host your images on a reliable service that can handle many simultaneous requests shortly after the push is sent. This prevents loading issues.
   • Using a Content Delivery Network (CDN) is highly recommended for performance and reliability. Examples include Amazon S3 with CloudFront, Google Cloud Storage with CDN enabled, Cloudflare R2, or similar services.

3. Dimensions and Formats:

   • Specific requirements for dimensions, aspect ratios, and supported file formats differ between iOS and Android. Please consult the official documentation for detailed specifications:
     • iOS10+ Media Attachment supported file formats
     • Android banner (push image) requirements

4. File Size and Quality: While adhering to the platform-specific limits mentioned in the documentation, aim for a good balance between image quality and file size to ensure images load quickly for users.

5. Testing: Always send test notifications to a real device to verify that your images or banners display correctly before sending to your broader audience.