title: How to select a portion of an image, crop, and save it using Swift?
body: <p>I am trying to create an iOS app using Swift to capture images and let the user save a selected portion of the image. In many cam based apps, I noticed that a rectangular frame is offered to let the users choose the desired portion. This involves either sliding the edges of the rectangle or moving the corners to fit the required area.</p>
  
  <p>Could you please guide me on how to implement that moveable rectangle and how to save only that piece of the image?</p>