Server & Client component for creating and rendering ~200 byte images (25% of original preview size).
Look at this blog post for more details.
For the iOS clients.
Include the NuGet package
Install-Package Q42.ImagePreview
var image = Image.FromFile("[path to your image]");
var body = ImagePreviewConverter.CreateImagePreview(image);
Store the body (byte[]). This is the information that you can send to your clients.
ImagePreviewConverter.Base64ImageFromBody(body)
Don't forget to add a blur to your images.