Usage is pretty simple & straightforward. Visit Pick&Zip (link provided at the bottom of the post), it will prompt you to enter Facebook login credentials. Once logged in, you can navigate through your friends albums.
You can instantly download the album in ZIP and PDF format. Just hover over the album and you will see a download icon on the bottom of picture, clicking it will provide you with two options ZIP & PDF respectively.
Specify either ZIP or PDF format.
Now just specify the location where you need to download the file in specified format.
Its that simple and easy!