If you're looking for another IceWarp alternative, Slack is a good choice. Slack offers a productivity platform for team communication with channels for collaboration, AI tools and virtual meetings that are encrypted. It's geared to help you communicate and get work done, in particular with remote workers, and can accommodate teams of all sizes with a range of scaling options.
Another good option is Coda. This all-purpose collaborative workspace combines documents, spreadsheets, apps and AI to help you get work done. With features like Writeups for decision documents, Hubs for centralizing information and Trackers for integrated spreadsheets, Coda helps you get work done without jumping from one tool to another. It integrates with more than 600 other tools, so it's very customizable and adaptable.
If you're specifically looking for a tool for project management and collaboration, ClickUp is a good option. It marries tasks, goals and chat into one service, with features like no-code automation and customizable views. ClickUp is designed to help teams work more efficiently and get more done, with pricing tiers that range from small businesses to large enterprises.
Also worth considering is RingCentral, an all-purpose cloud communications service. It links employee and customer communications with phone, message, video and contact center services. With features like AI-first video meetings, sophisticated business SMS and integration with Microsoft Teams, RingCentral can help you communicate more easily and work more productively in many industries.