You can either use your own photo albums and turn them into collages or the app can also pull photos from the albums of your Facebook friends and create a Photo Collage on Facebook that are visible to you.
It takes just a few steps to build your first collage. Authorize the app to reach your Facebook account, then select any of your photo albums (or that of your friends), choose a shape and your collage is ready. Hit the Share button to save that collage to your Facebook account or grab the permalink to share it by email.
The collages look impressive and if you don’t like the default layout, you can always move or cut any of the pictures on the pile. Here’s a quick video that shows how you can turn Facebook albums into collages.
Any photo collage that you create with Loupe is public and now there’s no option to change the visibility to private. Thus, if you have any private photos on Facebook that you don’t want the world to see, it may not be a good idea to turn them into collages because others may then find them through search engines.