Master Threads
Sales teams were losing deals because prospect replies were scattered across campaigns, subject lines, and channels. We designed Master Threads to automatically unify every conversation with a prospect into a single thread, regardless of where the reply came from.
The platform and the problem.
Master Inbox is a unified inbox platform for sales and lead-gen agencies. It aggregates replies from email, LinkedIn, and outreach tools like SmartLead, Instantly, and HeyReach into one workspace.
The core product worked: replies came in, teams responded. But conversations with the same prospect were fragmented. A prospect who replied to Campaign A on Monday and Campaign B on Thursday showed up as two separate threads. Teams were replying without context, duplicating outreach, and losing warm leads in the noise.
“I had a prospect who replied three times across two campaigns. Three different people on my team responded. The prospect got confused, we looked unprofessional, and the deal died. All because we couldn't see it was the same person.”
— Agency owner, 120+ mailboxes
Where conversations break.
We talked to agency owners managing 50+ client accounts and SDRs handling hundreds of active conversations daily. The same pattern emerged: fragmentation was costing them deals.
Duplicate outreach was common
Teams unknowingly contacted the same prospect from different campaigns. Prospects flagged it as spam, damaging sender reputation.
Context was lost between replies
An SDR responding to a Thursday reply had no idea the same prospect had already replied on Monday to a different campaign.
Manual merging didn't scale
Some teams tried searching by email or name to piece together history. At 500+ active conversations, most gave up.
Warm leads went cold
When a prospect replied across multiple threads, follow-ups were delayed or missed. No single person owned the full conversation.
One thread, full history.
A Master Thread shows every interaction with a prospect in chronological order: emails sent, replies received, LinkedIn messages, and automated follow-ups. Each message is tagged with its source campaign and channel so users understand the context without losing the unified view.
Unified timeline
All messages in a single chronological feed — no switching between campaigns or channels.
Source tagging
Each message shows which campaign triggered it and which channel it came through.
Cross-channel indicators
Visual indicators show when a conversation spans email and LinkedIn.
Retroactive merging
When the system identifies a match, it merges existing threads retroactively — not just new ones.
What changed.
72%
Reduction in duplicate outreach to the same prospect
40%
Fewer inbox threads to manage per workspace
2.4×
Faster average response time to warm leads
What we'd do differently.
We should have shown merge confidence scores earlier. Users wanted to know why threads were merged. A simple confidence indicator would have built trust faster.
Cross-channel threading should have been the launch feature. We shipped same-channel merging first and added cross-channel later. But cross-channel was the highest-value case — launching with it would have made a stronger first impression.