Here are the common centralized messaging options businesses use, grouped by purpose with short notes on strengths and when to pick each.

Team collaboration / internal chat

• Slack — Channel-based real-time chat, threads, voice huddles, rich app ecosystem and enterprise security/compliance options. Good for fast collaboration, lots of integrations, and companies that want a polished SaaS experience. (slack.com)
• Microsoft Teams — Deeply integrated with Microsoft 365 (Word, Outlook, SharePoint, OneDrive), strong meeting/voice/video features and admin controls; often chosen where Office apps are standard. (support.microsoft.com)
• Google Chat (Spaces) — Built into Google Workspace with tight Gmail/Drive/Meet integration; good if your organization runs on Workspace. (workspace.google.com)
• Twist — Async-first messaging (threads/inbox) designed to reduce interruptions and keep discussions organized — useful for remote or time-zone-distributed teams. (apps.apple.com)

Shared inboxes & unified internal/customer inbox (team handles email, SMS, chat, social in one place)

• Front — Shared inbox + collaboration features (assignments, internal comments, automation rules) that consolidate email, chat, SMS and social into a team workspace; strong for support/sales teams that rely on email and multi-channel workflows. (front.com)

Customer messaging / omnichannel support & sales conversations

• Zendesk Messaging / Zendesk Suite — Omnichannel support (web chat, in-app, social, phone), ticketing and agent workspace for scale; widely used by customer-support teams. (zendesk.com)
• Intercom — In-app and on-site Messenger focused on sales, product and support conversations with targeted messages and bots for automation and lead capture. (intercom.com)

Self-hosted / open-source (data control, regulatory or security needs)

• Rocket.Chat — Self-hosted or cloud; customizable open-source platform with E2E encryption options and omnichannel connectors (WhatsApp, SMS, socials). Good when you must control data or comply with strict regulations. (rocket.chat)
• Mattermost — Open-core, self-hosted Slack-style platform focused on security, compliance and integration into engineering/DevOps workflows; often used by regulated enterprises and government. (mattermost.com)

How to choose (quick guide)

• Small teams / startups: Slack or Google Chat for fast setup and many integrations. (slack.com)
• Microsoft 365 environments: Microsoft Teams for native Office integration and enterprise admin controls. (support.microsoft.com)
• Support-heavy teams handling lots of email/omnichannel requests: Front or Zendesk to centralize customer conversations and routing. (front.com)
• Regulated or security-critical orgs: Rocket.Chat or Mattermost for self-hosting, auditability and data sovereignty. (rocket.chat)

If you want, I can:

• Map the best 2–3 options for your exact needs (company size, channels you must support, compliance requirements, budget), or
• Produce a short migration checklist (data export/import, user provisioning, integrations, training) for moving from one platform to another.

Which of those would you like next?