Legal

Data safety

Effective: 10 August 2026 Version: 2.0 Scope: the Kalvien Chat Android app and its backend service. Purpose: the same declaration we make on our Google Play listing, published in full and in plain language.

The short version

  • No data is shared with third parties for their own purposes. Nothing is sold.
  • No data is collected for advertising, analytics, or profiling. There is no such code in the app.
  • All data is encrypted in transit. Messages and media are additionally end-to-end encrypted, so we cannot read them at rest either.
  • You can delete your account and live service data from inside the app. Safety reports and disaster-recovery backups follow the limited retention described in the privacy policy.
  • Private reactions, rich actions, stories, messages, and media are end-to-end encrypted. Channels, profile fields, reports, and routing metadata are readable by Kalvien.

A Play Data Safety form has fixed categories and no room for nuance. This page is the same declaration with the nuance restored — particularly the parts that are limitations.

01Summary of practices

Summary of Kalvien's data practices
PracticeKalvien
Data shared with third partiesNone
Data soldNone
Data used for advertising or marketingNone
Data used for analytics or profilingNone
Third-party analytics, ad, or crash SDKs in the appNone
Data encrypted in transitYes, all of it
Messages and media end-to-end encryptedYes
You can request account-data deletionYes, in-app and on the web; documented safety/backup retention exceptions apply
Account requiredYes — phone number and SMS code
Independent security auditNot yet
Source code publishedNot yet

02Every data type we collect

"Collected" means it leaves your device and reaches our servers. "Readable by us" is the column that most disclosures omit, and it is the one worth reading.

Data types collected, purpose, readability, and whether they are optional
Data type Purpose Readable by us? Optional?
Phone numberAccount creation, verification, anti-abuseYesRequired
Username & display nameApp functionality — how people find youYesRequired
Bio & avatarApp functionality — your profileYesOptional
MessagesApp functionality — deliveryNo — end-to-end encryptedCreated by you
Photos, videos, voice notes & filesApp functionality — deliveryNo — end-to-end encryptedCreated by you
Stories & private story interactionsApp functionality — sharing with authorised viewersNo — end-to-end encryptedCreated by you
Channel contentApp functionality — public broadcasting and moderationYes — channels are not end-to-end encryptedCreated by you
Message metadataApp functionality — routing and orderingYes — sender, conversation, timestampRequired
Private reactions & rich actionsApp functionalityNo — encrypted conversation eventsCreated by you
Unsent private-message draftsLocal composingNever collected — remains on your deviceCreated by you
Public encryption keyApp functionality — so others can encrypt to youYes — it is public by designRequired
Private encryption keyNever collected — never leaves your device
Conversation settingsApp functionality — pins, mutes, timers, read markersYesRequired for the feature
In-app contacts & blocksApp functionalityYesCreated by you
Session tokensApp functionality — keeping you signed inYesRequired
Push notification tokenApp functionality — new message alertsYesOptional — decline the permission
App-lock, biometric & decoy secretsApp functionality — device-level privacyNever collected — protected locallyOptional
Call metadataApp functionality — call setup, status, history and abuse preventionYes — participants, identifiers, timestamps and status; not live mediaCreated when you call
Abuse reportsSafety and moderationYesCreated by you

Data types we do not collect at all

  • Device address book / contacts. The app requests no contacts permission and has never uploaded or hashed your contacts.
  • Location of any kind, precise or approximate.
  • Live call recordings. Microphone/camera access occurs only when you start a voice note or call; live call media is not recorded or persisted by Kalvien.
  • Advertising ID, device fingerprint, or any tracking identifier.
  • App usage events, screen views, or behavioural analytics.
  • Crash logs or diagnostics sent to a third party.
  • Payment credentials. The app takes no payments. Amounts/names entered in encrypted bill-split messages are private conversation content.
  • Health, fitness, calendar, SMS message contents, call logs, or installed app lists.

03What end-to-end encryption covers

Private content uses authenticated X25519/XSalsa20-Poly1305 encryption. One-time prekeys provide forward secrecy for one-to-one messages and upgraded conversations refuse a legacy downgrade. Your private key is generated on your device, held in Android Keystore-backed storage, and never transmitted.

  • One-to-one message text — encrypted to the recipient's public key.
  • Group message text — encrypted under a group key that is sealed separately to each member's public key.
  • Private reactions and rich-message actions — hidden encrypted conversation events, not readable reaction rows.
  • Photos, videos, voice notes, files, captions, and albums — each file encrypted with its own key, which is then sealed to the recipients. Our storage holds an opaque blob.
  • Stories and their private interactions — story keys are wrapped only to authorised viewers.

For these, our servers hold ciphertext and no key that opens it. That is a property of key placement, not a policy we could reverse.

04What it does not cover

Stating this clearly is the whole point of publishing this page rather than only filing the form.

Readable by us, despite the app being "end-to-end encrypted"

Metadata. Who messaged whom, in which conversation, and when.

Channels. Channel posts, media, comments, reactions, and moderation data are broadcast content readable by Kalvien.

Call and message metadata. Participants, conversation/call identifiers, timestamps, routing and status must be processed to deliver the service. Live call media remains DTLS-SRTP encrypted and is not recorded.

Profile fields. Username, display name, bio, and avatar are stored unencrypted because they are shown to other users and must be searchable.

Abuse reports. What you write in a report is visible to us — necessarily, since the report is the thing that makes conduct visible in an encrypted service.

Security state and remaining limits

Forward secrecy and downgrade refusal. One-time prekeys protect one-to-one messages, and upgraded conversations do not silently fall back.

Safety-number verification. QR comparison lets users compare the identity keys shown by their devices.

Device privacy controls. Screenshot/screen-recording protection and optional passcode/strong-biometric/decoy locks are implemented, subject to Android platform and compromised-device limits.

No independent audit and no published source.

05Sharing and third parties

We share no data with third parties for their own purposes. We use a small number of processors who act on our instructions only:

Service providers and what each receives
ProviderReceives
RailwayHosting for the backend, database, and encrypted media — message content only as ciphertext
Google (Firebase Authentication and Cloud Messaging)Your phone number/sign-in data for verification; a device push token and content-free wake/call metadata for notifications
Configured TURN hostIP addresses, timing, and volume of encrypted DTLS-SRTP traffic when a direct WebRTC path cannot be established
CloudflareWebsite hosting; waitlist email if you submit one
ResendWaitlist confirmation email, if you join the waitlist

Push notifications carry no message content. The payload wakes the device; the app then fetches and decrypts locally. Google learns that a Kalvien notification was delivered and when, not who sent it or what it said.

06Permissions the app requests

Android permissions requested and why
PermissionWhyRequired?
Internet / network stateAccount, messaging, media, channels, calls, and syncRequired
Post notifications / vibrateMessage, call, and timed-event alertsOptional — the app works without it
Photo / media selectionChoosing an image to send or set as an avatar, only when you tap to do soOptional
MicrophoneRecording a voice note or participating in a call you start/joinOptional
CameraVideo calls, QR scanning, and camera flows you startOptional
Bluetooth / audio settingsCall audio routing and headsetsOptional
Foreground service / full-screen call intentMaintaining active calls and presenting incoming calls on supported Android versionsUsed for calls
BiometricOptional app unlock after explicit enrolmentOptional

Not requested, at all: device contacts, location, SMS reading, call logs, broad photo-library access, or background location. System pickers expose only the item you choose.

07Deletion

Settings → Delete account removes your live account, messages, media, keys, contacts, conversation settings, and sessions immediately, with no deactivated-account grace period. Safety reports and provider disaster-recovery backups follow the limited retention described in the privacy policy.

If you no longer have the app, use the process at kalvien.com/delete. Full detail on what deletion does and does not reach — including routine infrastructure backups — is in the privacy policy.

08Security practices

  • All traffic to our servers uses TLS.
  • Message and media content is end-to-end encrypted with vetted primitives via libsodium, not hand-rolled cryptography.
  • Private keys are stored in Android Keystore-backed encrypted storage and are not exportable.
  • App-lock, biometric, decoy, imported-archive, local-assistant, and backup secrets stay on the device unless you explicitly export a backup.
  • One-time prekeys provide forward secrecy and upgraded conversations reject downgrade.
  • Safety-number QR comparison verifies identity keys shown on each device.
  • WebRTC calls use authenticated signalling and DTLS-SRTP; Kalvien does not record live call media.
  • Media uploads are capped and stored as opaque ciphertext.
  • Disappearing messages are deleted server-side by a sweeper that runs every 60 seconds.

Report a security issue to security@kalvien.com. Good-faith research is welcome under the terms in our acceptable use section.

09Families and children

Kalvien is rated for users aged 13 and over (16 where local law requires) and is not designed for or directed at children. It is not part of Google Play's Designed for Families programme. Our child-safety standards and zero-tolerance CSAE policy are in the terms of service.