Source Wireframe Kit - Library of 537 blocks for desktop and mobile prototyping
Crello - A simplified graphic design tool with 10,000 free templates.
Platforma - Wireframe library of layouts and UI elements
Canva - Canva is a graphic-design platform with a drag-and-drop interface to create print or visual content while providing templates, images, and fonts. Canva makes graphic design more straightforward and accessible regardless of skill level.
iOS Wireframing UX Kit - An easy, speedy way to wireframe for iOS
Buffer - Buffer makes it super easy to share any page you're reading. Keep your Buffer topped up and we automagically share them for you through the day.