Help and how-to

The first screen asks for one thing: a name. First name is fine, up to 64 characters. It is what other phones show next to your messages; it is not an account and nobody checks it. Under it the app tells you what happens next: “Next, Yap asks for Bluetooth and nearby-devices access: that is how phones find each other without Wi-Fi.”

Join the mesh makes your key pair and opens the app. An empty name is quietly refused.

Privacy preferences opens the permissions door before anything is asked for. “Yap only asks for what you leave on. Anything off is never requested; you can still allow it later from the Mesh tab. The app works without any of these over the same Wi-Fi, by hand-carry and by SMS.”

The button at the bottom reads Enter your name first while the name is empty, Join without any permission when every switch is off, and Join with these otherwise. A permission you refuse is never asked for again by the app; it shows as a grey chip on the Mesh tab (see idle rungs) that opens the phone's settings when tapped.

Camera, microphone and location are asked for only at the moment a feature needs them: scanning a code, recording a voice note, sharing a place. Each is explained where it appears in this manual.

Home has four tabs along the bottom: Chats, Mesh, People and Files. The app bar shows the tab's title (Yap on the Chats tab) and under it a live line: “3 in mesh”, or “Hidden · 3 in mesh” while you are hidden. The small icon before it says whether any link is up.

The app bar buttons, left to right:

• Search (Chats tab only): replaces the title with Search chats. Matches names and previews. “No chats match “…”.” when nothing does.
• SOS (red): a tap only shows “Hold the SOS button to send an alert”. A long press opens the send sheet. See SOS.
• The eye: Hide me / Show me. One tap to vanish from nearby phones, one tap to come back. See Hiding.
• Menu (⋮), in order: New group, SOS alerts, Share the app, Photos & videos, Files & downloads, Chat settings, Battery & background, LoRa radio, Internet reach, Internet spools, Hidden chats, Safety, Help (this page), Screen lock, and Lock now once the lock is on. The three internet and radio items appear only in builds that carry those transports.

Lines that appear when they matter. A red strip under the app bar with a Retry button means the radios failed to start; the text is the error. A grey status pill on the Chats tab reads, for example, “Looking for nearby phones · 2 phones · Wi-Fi + Bluetooth” and expands to the ladder when tapped; it fades after six seconds. A one-line hint such as “Turn on Bluetooth to reach phones with no Wi-Fi” or “Allow nearby devices in Settings to reach phones with no Wi-Fi” appears when no link has come up for 30 seconds and a radio is idle, and goes the moment a link is up. A red SOS banner appears when someone nearby sent one.

Leaving. Pressing Back on a tab shows “Press back again to leave the mesh”; a second press within two seconds closes the app. While the app is open, or in the background under its “Yap is on the mesh” notification, your phone keeps relaying for others. Nothing runs once you close it.

The list holds three kinds of row. Nearby is always first and pinned: the public room of everyone in radio range, with a badge “N in range” and the last line said. Group rows show the group's icon and name with “Open · anyone nearby can join”, “Private · invite code only”, “Fenced · …” or “You left …”. Contact rows show the person, a blue tick if you verified them in person, the small icon of the rung they were last reached by (its tooltip reads “Reached by Bluetooth” and so on), a bell-off icon if muted, a pin if pinned, and an unread count.

Previews say who spoke: “You: …” for your own, and the sender's name in rooms and groups. Attachments preview as “📷 Photo”, “🎥 Video”, “🎤 Voice note”, “📎 name”, “🎵 name”, “📍 Location”, “📍 Live place”, “👤 Contact”, “📊 question”, “Sticker”, “GIF” and “Message deleted”.

Pinned chats sort to the top. Archived chats collapse into one row, Archived, with a count. Hidden chats leave the list entirely and live under Menu → Hidden chats. Long-press any row for its actions sheet (see the person sheet and group actions).

Under the list, Groups nearby lists open groups other phones announced, each with Join.

New chat opens a sheet: New group (“Open to anyone nearby, or private by invite”), Join a group (“Groups announced nearby, a scanned or pasted invite”), Scan a QR code (“A contact, a group invite or a message code”), NFC tap, By sound, Paste a code (“A code that came by any app or SMS”), and then your contacts, each marked “Nearby now” or “Out of range · messages wait”.

Your own card is first: your name, “No account · your key is you” (or “Hidden from nearby”), the first sixteen characters of your key, and My code.

Contacts — “Added by QR, NFC, sound or a pasted code. Messages to them are end-to-end encrypted.” Each row says “Nearby now” or “Not in range” and, if they let you sense them, the tier (“same room” and so on; otherwise “not around”). Tap to open the chat, hold for the person sheet.

Nearby now — “Phones linked to yours right now. Scan to make them contacts. Hold a name to block.” Each is “Verified contact” or “Not verified — nearby chat only”. A stranger here can only be reached in the public room until you exchange codes.

Blocked by the mesh appears only when the phones around you have voted someone out; see the mesh vote.

Add someone opens: Scan their QR code (“Line of sight: the surest way”), NFC tap, By sound, Paste a code, Scan any Yap code (“A group invite, a message code or an animated QR”) and Share the app for a phone that does not have it yet.

“Let someone scan this to add you as a verified contact. It carries your public keys only.” Under the QR:

• Copy code as text puts a “yap1:…” code on the clipboard: “Code copied. Send it any way you like; the other phone pastes it.”
• Share code hands the same text to any app through Android's share sheet.
• Share as link shares it as a “https://yapmesh.com/add#yap1:…” link, which opens straight into the app on a phone that has it.
• Beam (animated QR) shows the code as a changing sequence of QR frames (“frame 14”, “3 blocks · 441 characters”) for a camera that cannot read one dense code: “Point the other phone's Yap scanner at this. It keeps changing; the other phone stops on its own once it has enough.”
• Say it by sound plays it as chirps, if it fits: a full contact code does not (“This code is 325 bytes; sound carries 200 at most. Use Beam or Share instead.”), a short one does.
• NFC needs no button: “NFC: hold the phones back to back and the other phone reads this code from yours.”

The Reach me over the internet card at the bottom of My code belongs to the typed-address rung.

Every code is signed. A forged or damaged one fails its signature and is dropped; the app never adds a key it cannot verify. QR, NFC and sound are proximity channels: the tier they prove (“same table”, “same room”) is remembered and used by presence.

Nearby is the one public place: “Public to everyone in range · relayed phone to phone”. Everything said here is signed with the sender's key but not encrypted, and every phone in radio range, contact or stranger, can read it and pass it on. The header counts “N phones in range · public”. Your own messages show “seen by N”: the number of phones that acknowledged them, including hidden ones.

The empty states are honest about why: “Waiting for nearby phones — Open Yap on another phone within range. No Wi-Fi, no internet, no account.” when no phone is linked, and “Nobody has said anything yet — Everyone within radio range reads this room. Say hello.” when phones are linked but quiet.

The menu offers Search, Media & files, Mute notifications…, Auto-delete…, Export chat…, Share a file with everyone and SOS alerts; each is explained under chat tools. Holding the Nearby row on the Chats tab offers Go quiet (“Vanish from nearby and hold its messages; your phone keeps relaying”) or Come back.

While hidden the room replaces its composer with “You are hidden. Nobody nearby can see you, and you cannot post. Your phone still relays for the mesh.” and a count of messages waiting; Show me brings you back. Trying to post while hidden says “Hidden nodes do not speak to nearby”.

The abuse filter (on by default, see Safety) refuses abusive text before it leaves the phone: “Yap will not send that: it reads as abuse. Say it another way.”

The bar at the bottom has the text field (up to 4,000 characters, five lines before it scrolls), the @ button (“Mention someone”), the paperclip (“Send a file”) and the round button. The round button is a microphone while the field is empty: “Hold to record a voice note”, then “Recording… release to send”. It becomes Send once you type. A reply strip above the field shows who you are answering, with Cancel reply.

The paperclip opens six choices: Document, Photo or video, Location, Contact, Poll, Live place, and the reminder “Hold the microphone for a voice note”. Voice notes need the microphone (“Microphone permission is needed for voice notes”); a four-second note is about 20 KB. Location asks for the location permission at that moment and says “Location is off or was refused; nothing sent” if it cannot.

In a group, @ lists the members; a mention is bold in the bubble and the mentioned person gets a notification on its own channel. Typing sends a hint to the other phone every three seconds while it is within one radio hop, never further; the other phone's header shows it. Switch it off in Chat settings.

Poll asks for a Question (200 characters), two to twelve options (Add option), and Allow several answers. Send poll refuses an empty question (“Type the question first”) or a single option (“Pick one option”). The bubble reads “Choose one” or “Choose one or more”, shows a bar and count per option and “N votes”. Tap an option to vote; tap again to withdraw; in a single-choice poll a new vote replaces the old. Each phone counts the signed votes itself; there is no tally server. Partly verified

Hold any bubble. The sheet starts with six quick reactions: 👍 ❤️ 😂 😮 😢 🙏. Tap one to react; tap your own reaction again to withdraw it. Reactions pile up under the bubble; tapping the pile lists who reacted (“Nobody yet” when empty). Then:

Other things a bubble can show: “Forwarded” above a forwarded message; “Hidden by your abuse filter · tap to show” when the filter folded it; a date chip (“Today”, “Yesterday”, a weekday, “12 March”); and for group messages you sent, the per-member summary described under group chats.

A file bubble tells you exactly where the file is: “sending…”, “receiving…”, “downloading… 44%”, “Waiting for the file”, “2.1 MB · tap to open”, “1.3 MB · tap to play”, or a hold line such as “Tap to download”, “From someone not in your contacts · tap to download”, “Too large to download automatically”. A half-arrived photo or video never opens: the bubble waits for the last chunk before it draws anything. Open with another app hands a file to the phone.

Voice notes and any audio file play in the bubble: a waveform that fills as it plays, a clock, pause and resume, and tap-to-seek on the waveform. Photos open in the viewer with pinch-zoom up to 6×; videos play with scrub and replay, and a video the phone cannot decode says “This build cannot show the file itself.” with Open with another app.

Menu → Photos & videos decides showing, not fetching: Open when downloaded (“A photo or video shows itself as soon as the whole file is here.”) or Wait for a tap (“Bubbles stay covered. Tap one to open the photo or video.”) for when someone is looking over your shoulder. The same screen has Match my wallpaper (Android 12 and newer take the colours the phone picked from your wallpaper; off keeps Yap teal) and Link previews, off by default because fetching a preview tells that website your phone looked.

Every chat's ⋮ menu has the same first block.

Mute, auto-delete, typing hints, read-receipt switches, star, pin, forward, search, media lists, export and send-to-many are Built, not yet on a phone as of 11 September 2026; edit, pin, reply, react and polls were exercised between a phone and a browser node on that day.

Menu → New group or New chat → New group. Give it a Group name (“Chess club, Year 10 physics, Ward 4…”, up to 64 characters). Then:

• Open (default on): “Announced on the mesh; anyone nearby can find and join it.” Off makes it Private: “Not announced; people join by scanning or pasting your invite code.” A fenced group is always Private (fenced): “A fenced group is never announced; people join by invite and keep the key only inside.”
• Fence: “None: members keep the group wherever they go” until you choose one; see Fences.
• Retention — Messages disappear after Never, 24 hours, 7 days or 30 days, enforced on every member's phone; and Delete everything when I leave: “The thread and the group's files go from this phone on leaving”.

Create says “Created Ward 4. Phones nearby can now find it.”, “Created Ward 4. Share its invite code to let people in.” or, fenced, “Created Ward 4, fenced to …. Share its invite code to let people in.”. An empty name: “Give the group a name”.

Who is in a group is a signed record on every member's phone, not a server's opinion. Keys rotate when someone leaves or is removed; every sender has its own key chain per epoch, so a message read later never unlocks the ones before it. Verified on phones for open and private groups on three phones; fences Built, not yet on a phone.

Join a group offers Scan invite (“Point at the group's invite code”), Paste a code (“yapg1:…”) and Groups nearby: “Open groups other phones announced. Join to get the key.” Success is “Joined Ward 4”.

Invite someone (chat menu or group actions) shows the invite as a QR with Copy code as text. An open group's code “Anyone nearby can also find this group without a code. Scanning it just saves them the search.”; a private group's code “is the only way in. It carries the group key: anyone who has it can read the group.”

Members (the people icon in the chat) lists everyone with tags “admin”, “anchor”, “you” and “Where your last message stands with each of them”: “linked now”, “last message: read”, “Left”. In a fenced group a newcomer waits “At the door: tap their phone, chirp, or scan their code to let them in” until a member taps Admit: “Let Bilal in? Only after you tapped phones (NFC), chirped, or scanned their code in person. That is the proof they are inside.” → “Bilal is in; the key is on its way”. The admin can Remove from group: “The key rotates; they cannot read what is said from now on, and cannot re-join with the old invite.” → “Bilal removed; key rotated”.

The header shows the icon, name and “Open · anyone nearby can join · 3 members” or “Private · invite only · …”, the description if one is set, or the fence label, and a fence chip. The menu adds Group info, Invite someone, Members, Fence (fenced only), Share a file and Leave group to the usual chat tools.

Your own messages carry a per-member summary: “delivered to 3 of 5 · read by 2 · riding for 1”, settling to “delivered to all” and “read by all”; “nobody else in the group yet” while you are alone. A phone that hides receives but does not count. Verified on phones

Bars that can appear above the thread: “Amina at the door: tap phones, chirp or scan to let them in”; the pinned message; “No key yet. A member sends it after your join.” (the thread reads “Waiting for the key — A member will send this phone the key once your join reaches them. Until then nothing here can be read.”); “Only the admin posts here. You can read.”; “You are hidden. Show yourself to post.” with Show me; and the fence re-entry bar described below.

Leave group asks “Leave Ward 4? Its messages will be deleted from this phone. You can rejoin with an invite code.” — Stay / Leave. The row then reads “You left this group”.

A fence ties a group to a place. A member's phone that leaves the place loses the key; the rest of the group rotates it, so what is said afterwards stays unreadable on the phone that left. Built, not yet on a phone: fences pass every automated test and have not yet been tried on a phone.

The Label (“Zip 75001, Ward 4, Lincoln High”) is “A name for people. Never a boundary: the phone has no postal maps.”

Rules set with the fence on the New group screen: When a phone leaves the fence — Lock (“Drop the keys, keep the sealed messages, show “you left””) or Wipe (“Also delete the thread and the group's files from that phone”); Coming back in — Automatic (“The phone re-joins by itself when it is inside again”) or Needs a proof (“An NFC tap, a chirp or a QR scan with a member who is inside”); Grace period of 2, 5 or 15 minutes or 1 hour; Replay on re-entry of Nothing, Last 6 hours, Last 24 hours or Last 3 days.

Living inside one. The chat header carries a chip: “Inside”, “Outside 04:31” (the grace period counting down), “Unknown”, “Checking”, “Locked out”. The phone sends a liveness beacon every half grace period. When the grace runs out outside, a tombstone appears: “You left Ward 4 — This phone was outside for more than 5 minutes. Its keys were dropped and the rest of the group rotated theirs; the sealed messages stay here, unreadable.” (or, with wipe, “Its keys, thread and files were deleted”). Back inside, either “Back inside? The phone re-joins by itself.” with Re-enter, or “To re-enter: tap a member's phone, chirp, or scan their code.” The Fence page in the chat menu shows all of this plus Try to re-enter now.

“Whatever is shared here reaches every phone in range and spreads phone to phone. No Wi-Fi, no internet, no account. Drop a file to start.” Share a file picks any file; “Dropped notes.pdf: every phone in range gets it”. A file is cut into 16 KiB chunks under a Merkle root that is its name; every phone that holds a piece serves it, rarest piece first, and each chunk is proven against the root before it is kept, so a bad chunk is dropped before it is stored. Verified on phones: 5 MB in 320 chunks, 0 rejected, over Bluetooth alone in 2 min 53 s.

The Swarm panel shows “↓ 399.5 KB/s · ↑ 0 B/s” and “1 downloading · 1 phone sending to you” or “Nothing downloading”. Each file row shows its size and state (“Downloading 44% · about 5 s left”, “On this phone”, “Tap to download”), “Offered by …”, and “2 of 3 phones have it”. Holding a file offers Open and Share the file another way (“Quick Share, Bluetooth, email, any app — for a phone that is not on the mesh”). Tapping a waiting file when nobody has it says “Nobody in reach has this file right now”. While hidden: “You are hidden. Tap Show me to share files.”

Files in a group are encrypted with the group's key before they are chunked, so a phone that relays every chunk holds a box it has no key for. Files in a private chat are sealed to the one recipient.

Menu → Files & downloads. “A file offered by someone not in your contacts can wait for your tap. A file that waits is not on this phone until you ask for it.” Built, not yet on a phone

What opens, and what is caught. “Yap cannot scan files for viruses: messages are sealed end to end, so nothing between two phones can look inside, and there is no virus checker on the mesh.” Instead a received file is stored under its fingerprint, without a name the phone would act on, and when you open one the app reads its first bytes. An app installer, a program, a script or an archive is shown in red and needs a second confirmation whatever its name says:

• “This file installs an app on your phone. An app can read your messages, your photos and your contacts.”
• “This file is a program. Opening it runs code on the device that opens it.”
• “This file is a script: a list of commands for the device to run.”
• “This is an archive. What is inside cannot be seen until it is opened, and it may hold a program.”
• “This file may not be what it says it is.”
• and, when the name lies: “It was sent with a name that says otherwise: “holiday.jpg” looks like a photo, but the bytes are an archive”; the bubble carries a red “Sent as photo, really archive”.

The dialog offers Delete file, Cancel, Open anyway: “Deleted setup.apk. It will not be downloaded again.” Blocking someone deletes every file they sent and makes sure the same file never comes back from anyone else.

Long-press the red SOS in the app bar, or Menu → SOS alerts → Send SOS. “Every phone in reach is alerted, relays carry it 16 hops, and phones that meet later pass it on for a day. Signed with your name.” Add a line (“What is wrong and where you are (optional)”), keep or clear Include my position (on by default; it also sends your battery level), and tap Send SOS to every phone in reach. If location is refused: “SOS sent without a position: location is off or was refused”. Verified on phones on two phones on 7 September 2026.

Every phone that receives one shows a red banner at once, before it even reads it: “SOS from Amina, next to you, Ward 4 is flooding, tap for details” or “… 3 hops away …”. Hidden phones alert too, and acknowledge, so the sender's count is honest. SOS alerts lists every SOS heard with its sender, time, “mine” for your own, “next to you” or “2 hops away”, “battery 62%” and the position. “No SOS heard yet.” otherwise.

The map draws you in the centre, your direct neighbours on the first ring and their neighbours on the second: “Live · two hops deep” and “3 phones”, or “Alone · waiting for a link”. Hidden phones are drawn as “hidden”.

Ladder shows one chip per rung, lit when a link of that kind is up: Internet, Wi-Fi, Wi-Fi Direct, Bluetooth, SMS, Screen, Sound, Shared, LoRa. “Every link is ranked by rung; a message takes the best one and drops a rung when nothing comes back. When every radio fails the message is stuck and its bubble offers SMS, Share, Beam and Chirp; those rungs light up when used.”

Idle rungs. A grey chip such as “Bluetooth · Bluetooth off”, “Bluetooth · Bluetooth permission refused”, “Wi-Fi Direct · Nearby Wi-Fi permission refused” or “Wi-Fi Direct · No Wi-Fi Aware on this phone” explains why a rung is not running; tapping it opens the phone's Bluetooth or app settings. This is where a permission refused at first run can be granted later.

Counters. Mesh: Mesh size, Links, Neighbours, Speed. Carrying and relaying: Carrying for others (sealed messages this phone holds for people it may meet), Muled (delivered that way), Handed over, Ladder falls, Stuck, Hand-carried in, Relayed, Relayed for other groups, Received, Chunks in/out. Dropped: Duplicates dropped, Expired dropped, Bad signatures, Malformed, Oversize dropped, Blocked by mesh, Blocked dropped.

Radio is the transports' own words: “Looking for nearby phones · Looking over Bluetooth LE · Looking on Wi-Fi · Internet: no peers remembered · SMS: no numbers yet · LoRa: no board paired”, with “No link up yet” or “Up: Wi-Fi + Bluetooth”. Then the laptop switch (below), Neighbours (each with its transport, protocol version, “via relay” or “direct, punched”, and a tick if verified), Recent errors and the footer “Me: Zak · 770cf596f56fa1cd…”.

On the Mesh tab, Use Yap on a laptop: “Serves the app to any browser on your Wi-Fi or hotspot. No install.” Switch it on and the card shows “Open this on the laptop”, an address such as “http://172.168.0.111:7733” with a copy button (“Address copied”), and a QR. Join the phone's Wi-Fi or hotspot from the laptop, open the address, and the browser becomes its own node: it makes its own keys, has its own name, chats, files and map, and this phone relays for it. “The laptop becomes its own node with its own keys; this phone only relays for it. No Wi-Fi in the room? Turn on your hotspot and let the laptop join it.” Verified on phones; on 11 September 2026 the manual's own browser pictures were made this way and a poll was voted from the browser and counted on the phone.

What the browser copy cannot do, in its own words: send a private file (“Private files can be sent from a phone; the browser has no file path to seal”), start a hotspot or a gateway (“This build cannot host the gateway.”), lock with a fingerprint, use Bluetooth, SMS, NFC or LoRa. It reaches other phones only through the phone that serves it.

Menu → Safety gathers everything: Blocked people, Reports from this phone, the Abuse filter switch, Community standards, Help and how-to, Privacy policy, Terms of use, Child safety, Government and legal requests (“What Yapmesh holds about you: nothing. Transparency report.”), Contact and abuse reports ([email protected]) and Delete everything on this phone. Its footer: “Yapmesh has no accounts and no server, so there is no account to close and nothing of yours held anywhere else. Everything the app knows is on this phone. Copies of messages already delivered to other phones belong to those phones and cannot be recalled.”

Menu → Chat settings. Read receipts (on): “Off: nobody is told you read their message, and you stop seeing when they read yours. Groups always send them.” Show when I am typing (on): “A hint to the phone you are writing to, only while it is within one radio hop. Never stored, never relayed.”

Starred messages: “Hold a message and tap Star to keep it here.”, each with who and which chat. Send to many: pick people, write once, and “Sent to 4 people, each sealed separately”; the bookmark icon saves the names as a list (“Save as a list”, a chip “Ward team · 4” you can delete). It is deliberately not a broadcast list: nobody sees the list, and each copy is sealed to one person. Export all chats: “One JSON file with every chat, unencrypted, for you to keep. Files are not included.” → “Export all chats? The file is readable by anyone who gets it. Keep it somewhere safe.”

Menu → Share the app. On a phone from yapmesh.com the first card is This phone's installer: “Yap 1.1.1 (build 3) · 54.6 MB · offered to the mesh”, “Phones nearby on an older build are told about it and fetch it phone to phone, like any file.”, the Signer fingerprint, “You've given Yap to 2 people from this phone.” and Send the app with Quick Share / Bluetooth / any app. Then the hotspot card (above), From a laptop or any browser (“Turn on the gateway and a phone on the same Wi-Fi or hotspot can download the app from this one, no internet needed.” with Start the gateway), and Installers seen on the mesh. A debug build warns in red not to hand it to strangers.

The copy from Google Play shows Give Yapmesh to someone instead: “Send them this link. It opens the page that offers Yapmesh on Google Play and, for a phone with no Play Store, the signed app to download directly.” “Why not the app itself? This copy came from Google Play, and Play does not allow an app it distributes to hand out or update itself.”

Updates. When a phone nearby has a newer build, a card appears on the Files tab and on Share the app: “Update available: Yap 1.2.0 (build 4) · fetching from phones nearby”, then Install. Updates are accepted only from the same signer.

About (the ⓘ on Share the app) shows the version, the Signer fingerprint with a copy button, “The first 8 groups of the SHA-256 of the certificate this app was signed with. Anyone who gives you Yap shows the same line under “Share the app”; if the lines differ, it is not the same app. Updates are only accepted from this signer.”, What Yap is, the fence promise, how many people this phone has given the app to, and the links: Help and how-to, Privacy policy, Terms of use, Community standards, Safety: blocked people and reports, Child safety, Open-source licences, Support ([email protected]).