Mockuuups Studio - Fast and easy way to create product mockups on macOS, Windows and Linux.
vym - VYM (View Your Mind) is a tool to generate and manipulate maps which show your thoughts.
Mockups Design - Mockups Design is the most leading web-based application that comes with a vast collection of creatively design mockups for all kinds of products and devices.
Freeplane - Freeplane is a powerful and free software for building mind maps.
Mr. Mockup - Mr.
SuperNotecard - Introducing SuperNotecard. SuperNotecard is an online writing tool that features virtual notecards to help arrange facts or scenes, track details, organize paragraphs, and clarify your composition process.