Customizr, a WordPress theme, “recommends” Nimble Page Builder in an advertisement in the WordPress dashboard after you upgrade Customizr to the latest version. Below is what the ad said.
“Nimble Page Builder is a free, easy to use yet powerful page builder used by 30K+ WordPress websites. It allows you to create mobile ready columns layout, drag-and-drop modules like post grids, buttons, widget zones, maps, icons, or beautiful pre-built sections with a parallax background, into any page of your site. Nimble Builder uses the live customizer which is the native WordPress interface for real-time design. The plugin has been designed to integrate perfectly with the Customizr theme. Lightweight and safe.”
I’ve never used this so I can’t comment on it.