Tap the Share button on the bottom of the page. It looks like a
square with an arrow pointing out of the top.
In the list of options that appear, scroll down and tap on Add to
Home Screen. The Add to Home Screen dialog box will appear.
Choose a name for the website shortcut on your home screen.
Click Add when you're done. Safari will close automatically, and
you will be taken to where the icon is located on your iPhone’s or
iPad's home screen.
Now just tap the new "app" or shortcut on your home screen, and it
will open the website in its own navigation window, independent of
what you have open in Safari.
Android
Tap the menu icon (3 dots in upper right-hand corner) and tap Add
to home screen.
Choose a name for the website shortcut, then Chrome will add it to
your home screen.