Figma
Figma is a vector graphics editor and prototyping tool which is primarily web-based, with additional offline features enabled by desktop applications for macOS and Windows. The Figma mobile app for Android and iOS allow viewing and interacting with Figma prototypes in real-time on mobile devices.

Figma: the collaborative interface design tool.
Build better products as a team. Design, prototype, and gather feedback all in one place with Figma.
Miro
A whiteboarding platform, Miro helps your team go beyond brainstorming, with a wide variety of tasks that require collaboration: workshopping, strategy mapping, Agile ceremonies, UX research and design, product development, customer discovery and process visualization.

The Visual Collaboration Platform for Every Team | Miro
Scalable, secure, cross-device, and enterprise-ready team collaboration whiteboard for distributed teams. Join 35M+ users from around the world.
LucidChart
Lucidchart is the intelligent diagramming application that brings teams together to make better decisions and build the future.