Whimsical Wireframes - Lightning fast wireframing with real-time collaboration.
Mediamodifier - Create beautiful designs and product mockups in seconds.
Adobe XD - Adobe XD is an all-in-one UX/UI solution for designing websites, mobile apps and more.
Mockuuups Studio - Fast and easy way to create product mockups on macOS, Windows and Linux.
Userflows - Automatically generate user journeys
mockDrop - Is a webapp for creating free device mockups including your screenshots.