AN UNDERGROUND
POSTAL SERVICE

What it is

deadletter is a hidden layer on top of the city. Messages pinned to exact places. Only people who are at those places can collect them.

Inspired by W.A.S.T.E., the secret postal service in Pynchon's The Crying of Lot 49.

Leave a message

Open the DROP tab. Write something. Pick a paper stock and a stamp — or don’t, and luck picks the stamp. Hold your phone up and tap a real surface — a bench, table, counter, or even floor. The message is anchored there.

Your drop waits at that exact spot for whoever it’s addressed to — everyone, one name, or your circle. Reading it still takes being within 15 meters.

Copy a song or playlist link from Spotify, Apple Music, or YouTube and paste it into any letter — it arrives as a playable card.

There is no unsend. Once you leave a drop it stays until the lifespan you chose runs out. Say it like you mean it.

Find a message

Open SCAN. If you’re within 15 meters of a drop, hold your phone about an arm’s length from a flat surface — a table, counter, bench, or floor. Tilt the camera slightly so it sees the surface at an angle. Messages appear in AR on that surface. Tap to open.

Smooth, unbroken surfaces work best. If the scanner says “FINDING SURFACE…” for a while, try moving closer or aiming at something less cluttered.

Message drops don't show up from far away. You have to physically go there. That's the point.

Keep what you collect

Tap a message to collect it. Everything you've found lives in the FOUND tab. Re-read any time.

Circles

CIRCLES are private groups. Only members see drops made to a circle. Create one, invite friends with a code, and drop messages only they can find.

A circle that goes thirty days without a single letter is deleted.

Direct messages

Type a username as the recipient. The drop is end-to-end encrypted — only that person can decrypt it. They still have to physically go to the location to find it.

A direct drop is a sealed letter — not even we can open it. The keys never leave your phone. You can only write to someone whose code you have scanned in person — trade codes face to face, and the letter box opens.

Replies

Tap REPLY on any drop you find. Your next drop is pre-addressed as a direct message to the author — you still write it yourself and drop it at a real place. The author gets a notification.

Conversations happen across geography.

Block & report

When you open a drop, you’ll see BLOCK and REPORT. Block hides all drops from that author, everywhere. Report flags content for moderation.

Frequently asked

Do I need to sign up?

Not to explore — tap TUNE IN and you can find and read drops anonymously. To leave any drop (open, direct, or circle) you sign in with Google, Apple, or an email link and claim a username. This keeps spam out.

Does it use my data?

GPS, yes — for placing and finding drops. Nothing is sold. Direct drops are end-to-end encrypted; we can't read them. They require an in-person code exchange first. Circle drops are encrypted for their members — though not end-to-end during the beta: we hold a circle recovery key (see the privacy policy). Open drops are postcards — public, unencrypted, readable by anyone who finds them.

What if I'm in a quiet area with no drops?

Be the first. Leave something at a coffee shop, a park bench, your building's stoop. Messages persist. Someone will find it eventually.

Can I see a drop without being there?

You can see it exists on the map. You can't read it until you're within 15 meters and scan.