Here we have a visual diff tool called TwentyTwenty that highlights the difference between two images. Created by Zurb as a new addition to their playground.
I have created one way back before. If you wanted to know how it work, you can visit : Create an Attractive Before and After Photo Effect with jQuery. Mind you though, it's dated but it still work perfectly.
- Simple markup and implementation
- Responsive and functional on all devices
- Doesn't require images to work
- Work well with its foundation framework