Tetrisly - Starter kit for design systems and wireframes builder (Sketch/Figma)
MDB for Angular - Material Design + Angular done right
Material Design Icons - 750 Free open-source glyphs by Google
Invision - Prototyping and collaboration for design teams
Material UI - A CSS Framework and a Set of React Components that Implement Google's Material Design
Platforma for Android - The ultimate wireframe kit for your next android app