Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Visily - The easiest and most powerful wireframe software for agile teams.
Adobe XD - Adobe XD is an all-in-one UX/UI solution for designing websites, mobile apps and more.
PSD to Sketch Design Converter - Convert a Photoshop design to a layered Sketch file for free
UXpin - Design is really about solving problems. UXPin is the UX Design Platform that gets that right.
Learn SpriteKit by Design+Code - Make a platformer iPhone game from scratch in Swift 4.