If you have enabled downloads in a web gallery, when viewing on mobile your visitors will have the ability to save an image directly to their device.
To save an image, click on the download icon in the picture.
Next, you’ll see a pop-up with following instructions (hopefully this will help your clients). To download the image on a mobile device, tap and hold the image when it opens in the next screen after clicking “Continue”.
**Note: iOS 13 now allows you to directly download images in Safari by clicking the "View" button or "Download" button.**