I use UIPastboard to copy and paste a retina image into a keyboard extension, but when pasted into notes or messages, it appears as an image without a retina.
Below is my code that copies the image to cardboard.
UIImage *retinaImage = [UIImage imageNamed:@"retinaimage.png"];
NSData *imageData = UIImagePNGRepresentation(retinaImage);
[[UIPasteboard generalPasteboard] setData:imageData forPasteboardType:@"public.png"];
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