Fragment is a program that comes as an alternative to using Preview, Mac's default image viewer, for examining and editing pictures on your computer. The utility supports various image formats, lets you preview your pictures in slideshow mode, and offers you a simple way to share your favorite photos with your Facebook or Twitter friends.
You can open a single image file or import a folder that contains pictures. The app lets you preview the photos in slideshow mode and allows you to choose from multiple transition effects. Unfortunately, not all transition effects are available for free. You need to make an in-app purchase in order to unlock all slideshow effects.
In my testing, I had to go to the homepage of the developer to figure out how to handle some of the app's features. To be more exact, I wasn't sure how to rotate the imported images. And since the program doesn't feature a help guide, I looked for the info I needed on the product's website. From there I learned that you can rotate images by hitting the Shift+R keys. You can also click the white bar from the right side of the imported image and select the image rotation option (I didn't see the bar until I found this info on the website). Hence, you should read the information from the homepage of the developer to learn how to handle this utility.
Personally, I think Preview is a far better choice for checking pictures than Fragment is. It works with many image formats, is very intuitive, lets you edit and convert pictures, etc.