Popup Maker - Advanced Theme Builder 1.2.0

Keep users from heading for the nearest close button – create awesome popups instead.
The Advanced Theme Builder Does Both of Those
Produce powerful and influential popups with the Advanced Theme Builder: go the extra mile by creating and uploading your background images.

Create awesome effects by using .png images with transparency and tweaking the background overlay color and opacity itself.

This is the best feature to give your popups that extra something that keep your users engaged as opposed to looking for the nearest close button.