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MailerSpark

Unibox

Every reply,
one inbox.

The Unibox pulls every reply from every connected inbox — Gmail, Microsoft 365, IMAP — into one place. AI sorts the Interested from the noise. Your team works one list, not six.

Start freeCold outreach

Syncs every 60 seconds · OpenAI / Ollama / heuristic

Unified reply thread

One thread per prospect,
regardless of inbox.

Whether the reply landed in alex@yourco.com, sales@yourco.com, or outreach@yourco.com, you'll see it in the same thread — with the full conversation history, the sequence step that started it, and the lead record next to it.

  • Gmail OAuth
    Native integration using Gmail's history API. No password stored.
  • Microsoft 365 OAuth
    Microsoft Graph delta queries. Mail.ReadWrite scope only.
  • IMAP for the rest
    Any provider that speaks IMAP — custom SMTP relays, Fastmail, ProtonMail Bridge, etc.
  • 60-second sync
    Workers run on a BullMQ schedule. Replies show up in the Unibox within a minute.
Unibox · 7 unread
AI ON
P
Priya R.
Re: Quick question about Acme
Interested
M
Marcus T.
Out next week
Out of office
A
Alex K.
Re: Q4 update
Interested
n
noreply@vendor
Auto-Reply
Auto-reply

AI reply classification

Reply, classify,
act.

Every inbound message is auto-classified into one of five buckets. Your team works the Interested pile. The rest is archived but searchable for follow-up or analytics.

  • Five categories
    Interested · Not Interested · Out of Office · Wrong Person · Auto-Reply.
  • Three backends
    OpenAI (your key), Ollama (local), or the heuristic fallback. Pick per organization.
  • Lead status sync
    Classified replies can auto-transition leads from contacted → interested. The CRM stays in sync.
  • Manual override
    If the AI gets one wrong, reclassify and the model learns (heuristic only).
Classification result
"Hey — actually yes, can you send me a deck? Would love to loop in our CTO next week. Tuesday or Wednesday works."
Interestedconfidence 0.96 · OpenAI gpt-4o-mini
Lead status auto-updated: contacted → interested

Reply where you work

Reply from the Unibox.
No inbox switching.

The Unibox isn't a read-only feed. You can reply directly — and MailerSpark routes the reply through the same inbox the original came from, so the prospect sees a real conversation.

  • Threaded context
    Send a reply, get a response, send another — all from the Unibox thread view.
  • Per-inbox identity
    Replies go out from the inbox the prospect originally wrote to. No 'sent from a different address' confusion.
  • Cc / Bcc + signatures
    Per-inbox signatures and per-reply Cc/Bcc. Works the way your team already works.
P
Priya Ramaswamy
priya@acme.com · via sales@yourco.com
Interested
"Yes, can you send a deck? Would love to loop in our CTO next week."
Replying via sales@yourco.com
"Sounds great Priya — attaching a deck. I'll send a calendar link shortly for next week."

Reply analytics

Know what's working

The Unibox isn't a black hole. Every reply rolls up into campaign analytics: reply rate, positive reply rate, time-to-reply, and per-inbox health.

47%
Reply rate
vs ~8% industry avg
2.4h
Median time to reply
from first send
61%
Positive reply rate
Interested / 47% reply rate

Growth plan and above

The Unibox is on Growth and above.

Pairs with cold outreach sequences. Also useful on its own if you want one inbox for replies from every team member's mailbox.

Start freeSee pricing
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