The case itself is a thin/hard/clear plastic with a BEAUTIFUL floating liquid with glitter and stars on the back of it.
I found this on Amazon and you can check them out here. There are over 42 different options to choose from - every different color glitter you can imagine, different *bling* floating about (stars, butterflies, hearts, etc). They are SO pretty! They make them for the iPhone 5 and 6 I know, maybe other makes and models as well. If you just search in the search bar on Amazon's website for 'glitter iPhone case' you will see them immediately! (Or click the links in this blog post and they will take you straight there).
Here is a video of what the case exactly looks like when you move your phone:
Hope you enjoyed! Let me know if you get one of these and what color you picked out! I also REALLY love the Stars: Silver one with the silver glitter and the varying shades of purple heart confetti, and the Beads: White one with the white beads and varying colors of star confetti.