Swift如何修改从移动相机拍摄的图像中的exif信息

I use UIImagePickerController to pick images in my iOS App and I know exif info can be got by info[UIImagePickerControllerMediaMetadata]. But when I upload my image to my server by UIImage, most of exif info has been striped. I wonder whether I can add exif info to my image in Http request(image uploaded as jpg after that). If not, how should I solve this problem? I wanna change Make, Model attributes(in other words, what device was used to take this picture)I use UIImagePickerController to pick images in