Froala Design Blocks - 170+ free responsive design blocks based on Bootstrap 4
nodo - Manage your daily tasks in the command line
Webflow Flexbox UI Builder - Build flexible, responsive layouts — without writing code
Moodie - Track and change your mood throughout the day
Antetype - Antetype - Layout aware User Interface Design - responsive and future proof.
Simple Grid - Responsive & lightweight CSS grid for your website.