If you have an iPhone, there are a few ways to change the file extension of a file. This is especially important if you want to change the file extension for a document or image that is stored on your iPhone. To change the file extension on an iPhone, follow these steps:

  1. Open the File menu and select “Open in new window.”
  2. Type “extension” into the text field and press Enter.
  3. The “Extension” dialog will appear, shown below.
  4. In this dialog, select the desired file extension and press Enter.
  5. The new file extension will be displayed in the text field next to “File.”