Responsive Viewer - View multiple screen dimensions in one view
Parade - Easily create parallax scrolling animations on iOS
Responsinator - Designed to test responsive websites on different devices.
Tipsly - Tipsly.io is a french toolbox with more than 100 free tools.
Multi Screen Test - Test your site at different screen resolutions & devices.
DesignValley - Discover, vote and share your favorite design tools 🥇