From the website:
The easiest way to play tabletop roleplaying games online, free.
Astral can support virtually any tabletop roleplaying game. Get started quickly with built-in support for most popular game systems.
Build epic battlemaps using Astral's enormous collection of scenery, props, and tokens or upload your own. Pro users gain access to over 16,000+ assets and fresh new packs every month. Add weather, visual effects, triggers, and so much more with easy-to-use tools.
Astral is browser-based and uses the latest technology to streamline your storytelling experience. Connect with your party online and run your campaigns however you like. Astral offers tools optimized for phone, tablet, and desktop devices, no installation required.
Astral shut down permanently on August 30, 2022.