InVision – “Powerful design and prototyping tools. Get high-fidelity in under 5 minutes. Upload your design files and add animations, gestures, and transitions to transform your static screens into clickable, interactive prototypes.”
This site has one of the best newsletters out there. Their newsletters are mostly centered around design and UI/UX/UXD. They put a lot of great information, tutorials, business info, and freebies, into their newsletters. They also add links to some inspiration for designers which is awesome. Their freebies include things like ebooks, icons, design/develop stuff, info, and jobs.