Sender Zero.
You don't reach zero emails. You reach zero undecided senders — and the past sinks on its own. Every decision you make is about a whole sender, past and future, so forty decisions clean a mailbox of sixty thousand.
Every demo below is the real design, wired to a small pretend mailbox. Nothing you do here touches anything.
Inbox5 chats
Drag a row. Right to left: Archive — keep pulling and it becomes Trash. Left to right: Snooze, then Important. Or press:
Why every inbox ends up a heap
Sixty thousand emails is sixty thousand decisions.
Everyone with an old mailbox has tried "one day I'll sit down and clean it". The day never comes, because the job is the size of the heap. Inbox Zero fails the same way: it counts emails, so the goal is always sixty thousand steps away.
- 1Count senders, not emails. Sixty thousand emails is perhaps fifteen hundred senders. The ones on your first pages this month: about forty.
- 2One decision covers everything they ever sent, and everything they send next. In Korro a chat is a sender, so a swipe on a chat is a decision about all of it.
- 3The past sinks. Senders who never write again never need a decision. Nothing is deleted; it simply stops being in your way — and search still finds it.
A mail clientdecides per email
Korrodecides per sender
One row. One swipe. All 116 gone from your Inbox, and the 117th never arrives in it.
How the app does it
Korro keeps a notebook. Gmail does what it says.
Gmail has no memory of senders — only of emails. So Korro keeps one line per sender: nothing yet, archived, trashed, or kept. Every time a mail arrives, Korro reads that line first and acts in Gmail itself, within seconds, before the mail reaches your Inbox anywhere. Pick a decision and deliver a mail:
Your Gmail inbox3 mails
Korro Inbox3 chats
Korro enforces the notebook itself rather than writing Gmail filters, so it never asks for another Google permission and never fills your Gmail settings with rules. If Korro is ever down, the double-check on its return puts things right. And if you move a mail back by hand in Gmail, that wins: the sender is un-archived.
To decide7 senders
Senders from the last 30 days you have not dealt with. Keep them, or swipe them away.
Tap ✓ to keep a sender, or drag a row away. Watch the number.
The one number Korro keeps for you
To decide.
A row at the top of your Inbox: the senders from the last thirty days you have not said anything about yet. Not the people you've written to — writing is a decision. Not the chats you starred, snoozed, archived, trashed or put in a group. Just the ones still waiting for a word.
- ✓Keep — they're fine, leave them where they are.
- ←Archive — out of Inbox, past and future, still searchable.
- ⇐Trash — everything they ever sent, and everything they send next. Restorable while Gmail keeps its Trash.
The number reaches zero in days, then stays near zero: new senders arrive one or two a day. The senders you never open rise to the top and say so — "6 mails, none opened".
Korro doesn't guess — it notices what you do
What counts as a decision.
You never file anyone. Your own behaviour is the address book. Any of these takes a sender off the list for good:
From any of your Gmails, ever. A reply, a new chat — Korro already knows all your sent mail.
Important is Gmail's star; a snooze says "bring them back on a date". Both are a yes.
The two swipes. The whole sender, past and future.
Family, Work, Clients — pills at the top of Inbox. A task from their mail counts too.
The explicit yes, when none of the above is true but you still want them.
You open things to see what they are. Looking is not deciding.
Keep wears off. Keep a newsletter in June and then never open it again? After ten unopened mails it comes back to ask once more:
Once it's clean, it gets useful
Groups, without filing.
Family, Work, Clients — your own names on chats, as pills right after Gmail's categories. One tap narrows Inbox to those people. Korro's own; nothing changes in Gmail. Try the pills:
Inbox6 chats
How it compares
Other methods lift the heap. This one lets it sink.
Counts emails and asks you to empty the inbox every day. Sender Zero counts senders and asks you to decide about each one, once.
Ask you to predict what you'll want before it arrives. Sender Zero asks after the first mail, when you can see what it is.
Leave the list for you but keep the history in the way. Trash does both: leaves the list when it can, and moves everything they ever sent out of sight.
Guess. Sender Zero remembers what you decided and does exactly that, every time — and says out loud when it notices something ("6 mails, none opened").
How to do it
An afternoon, then a minute a day.
Day one
Open Inbox. Tap "To decide".
It says 38, or 60, or 12 — the senders from the last month you never dealt with. Go down the list: ✓ the ones you want, swipe the rest. The ones you never open are already at the top.
- Right to left: Archive. Keep pulling: Trash.
- Left to right: Snooze. Keep pulling: Important.
- Undo is right there on every one.
Every day after
One swipe when the row appears.
New senders arrive one or two a day. The row shows up, you decide, it goes away. Your first pages stay the way you left them, because nobody you decided about comes back uninvited.
- A person you swiped away lands quietly in Archived — no notification.
- Want them back on a date? That's Snooze.
Changed your mind
Everything undoes.
Nothing here is a one-way door.
- Undo on the toast, right after.
- Move to Inbox on an archived chat forgets the decision.
- Trashed senders in your Gmails sheet: Restore brings back whatever Gmail hasn't emptied yet.
- Write to someone you archived: they're back.
- Move a mail back by hand in Gmail: that wins too.
Forty decisions, not sixty thousand.
Korro is in private beta. If you have an invite, sign in and tap "To decide" — the afternoon starts there.