Inbox accountability for tiny B2B teams.

Turn shared customer, sales, and operations inboxes into an accountable work queue without forcing a small team into a full CRM migration.

Join the private waitlist

Interest signal: send a short email from your work address. No automated sending is part of the initial validation test.

Daily founder queue

Open work, stale threads, owner suggestions, and risky revenue conversations in one reviewable queue.

Hot lead waitingSales thread stale for 22 hours. Owner suggested.
Onboarding blockedCustomer asked for next step inside a long thread.
Invoice questionRevenue-relevant reply needs review today.

The leak

Shared inbox work looks simple until everyone assumes someone else replied. Leads wait, renewals sit, and founders scan every inbox manually.

The narrow wedge

InboxOS starts with Gmail or Google Workspace teams of 3-20 people that run high-value inbound conversations from shared mailboxes.

The promise

Connect one inbox or label, review extracted actions before anything is sent, and measure response time, missed follow-ups, and founder triage time over 14 days.

Built for teams before a full CRM migration.

Founder-led B2B services teams, small agencies, niche SaaS consultancies, logistics and operations-heavy SMBs.

What the queue shows

  • Who owns each thread.
  • What action is needed next.
  • Which customers or leads are waiting.
  • Which messages are stale or revenue-relevant.

What it avoids

  • No broad platform build before demand.
  • No automated sending in validation.
  • No replacement claim against Salesforce, HubSpot, Intercom, or Zendesk.

Join the validation list

Validation counts as visits to this page and work-email interest sent to ventures@cassien.ai. If your team matches the pilot profile, we will contact you after review and approval.

Join the waitlist

Idea slug in subject: idea-01-inboxos.