I found what to do ..
I used to do it
UIImage* image1 = [UIImage imageWithData:imageData1]; NSData *imageData = [NSData dataWithData:UIImageJPEGRepresentation(image1, 1];
I changed it to
UIImage* image1 = [UIImage imageWithData:imageData1]; NSData *imageData = [NSData dataWithData:UIImageJPEGRepresentation(image1, 0.5];
This change is the compression quality of the image attached when it is “1”, this is the maximum size, and by default, the MFMailComposer function prompts the user to resize the image to a fairly large size by default. If you change this to “0.5,” the image will be compressed and the size will be smaller and it will not ask the user to resize.
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