If you're looking for an alternative to Velt, Liveblocks offers a full developer toolkit to build high-performance collaboration into your products. It works well with mainstream frontend frameworks, offering features like real-time presence, broadcast, comments and sharing, and is good for document editing, creative tools and whiteboards. Liveblocks is good for a broad range of use cases and has customizable pricing plans, including a free starter plan.
Another good option is Tiptap, a library of content editing and real-time collaboration tools. It includes a headless content editor and collaboration framework for custom content experiences. Tiptap supports real-time collaboration, AI-generated content, version control and a variety of use cases like custom content sites, collaborative platforms and drawing tools. It also can be used as an on-premises or cloud service with flexible pricing.
If your team is focused on commenting and task management, Commented is a collaboration and commenting tool to help keep project communication on track. It offers features like rich annotation, task assignment, public commenting and mobile SDK integration. The tool is designed to help teams work more efficiently and speed up product development and delivery, so it's a good fit for product managers, developers and designers.