Save Photo to Library - Swift 3

savePhotoToLibrary.swift

func savePhotoToLibrary(image: UIImage) {
    let photoLibrary = PHPhotoLibrary.shared()
    photoLibrary.performChanges({
      PHAssetChangeRequest.creationRequestForAsset(from: image)
    }) { (success: Bool, error: Error?) -> Void in
      if success {
        // Set thumbnail
        self.setPhotoThumbnail(image: image)
      } else {
        print("Error writing to photo library: \(error!.localizedDescription)")
      }
    }
  }