Last updated: 11 November 2026 · Cepho (Denmark / EU)
Cepho runs cepho.cloud, the Cepho mobile app, and the Cepho extension. This page covers what personal data we process and why, under the GDPR.
Account
Email address, display name, Firebase authentication identifiers, account creation date.
Project data
Files you sync to Cepho cloud, chat messages and AI replies, and sync metadata (paths, timestamps, snapshot IDs). Stored in Firebase Storage and Firestore.
Beta program
If you join the beta: usage counters (messages sent / remaining), beta status, and approximate country/region from your IP at registration. We do not keep your precise IP.
Waitlist and share campaign
Email you submit to the waitlist. For the share campaign: your email and the link to your post.
Download tracking
Anonymous clicks on beta download pages (timestamp and approximate country only, no personal identifiers).
Billing
Payment status and plan via Stripe. We never store full card numbers. Stripe handles payments.
Technical
Device type, app version, extension version, and crash details if you send feedback.
Cookies and site analytics
Essential cookies on cepho.cloud for login and the product. We use Google Analytics 4 to see how the site is used (pages, approximate location, device/browser). No advertising trackers. Google's policy: policies.google.com/privacy.
We process data to run cloud sync, AI chat, billing, and support (contract and legitimate interest). Beta and waitlist data rest on consent at sign-up. Marketing email only with consent.
You own your code. Cepho is a sync and interface layer. We do not claim rights to your files. You are responsible for what you upload. Do not put unlawful material, secrets, or credentials in a Cepho workspace.
When you sync a project, file contents go to our Firebase backend so your devices stay in sync. Firebase security rules stop other users from accessing your files. Rules are not the only protection. Encrypted workspace encrypts file contents at rest, so once a file is stored as ciphertext, Cepho operators cannot read those contents without your passphrase or an unlocked device key. Section 4 covers live sessions, leftover plaintext during migration, and AI.
We also skip common secret-file patterns from sync (for example .env, private keys, credential filenames). That lowers accidental uploads. It is not a substitute for Encrypted workspace.
Three different situations, so the wording does not collide:
ceph1:). Cepho operators cannot read those stored file contents without your passphrase or an unlocked device key.Encrypted workspace (On by default for new projects; cannot be turned Off in the current product). File contents in your Cepho project are encrypted with Cepho's own encryption before they are stored in the cloud. That applies on both phone and computer (same Cepho encryption, ceph1:). Project file contents are encrypted on your devices before upload to Storage and in pending-change payloads. Your account passphrase is never uploaded. We store a verifier and per-project wrapped keys in Firestore so another of your devices can unlock. Unwrapped keys live on your devices (mobile SecureStore / OS keystore; on PC under a local Cepho encryption file after unlock). On the phone, the passphrase may stay in SecureStore across normal sign-out so the same device does not re-prompt. A new device, uninstall, or PC still needs unlock. If you lose the passphrase and have no unlocked device left, neither you nor Cepho can recover the ciphertext.
Phone encrypt limit (1.5 MB). On mobile, the Cepho app can encrypt files up to 1.5 MB. The limit exists so the phone does not run out of memory when large project files are downloaded and rewritten. Under 1.5 MB: the file is encrypted on the phone and stored in the cloud as ciphertext. Over 1.5 MB: the phone skips that file on the mobile encrypt/migration path (the same applies to heavy binary file types the app does not need to read as text, for example zip, video, and large builds). Larger project files are still encrypted. When the project syncs via Cepho sync on a computer, Cepho also encrypts files over 1.5 MB before they are stored in the cloud. It is the same Cepho encryption; the phone simply does not handle the largest files locally. Once files are encrypted in the cloud, they remain as ciphertext. You unlock the project with your passphrase on the device.
What stays visible anyway. Project names, paths, sizes, timestamps, sync IDs, connection status, and similar metadata can still appear in Firebase. Chat messages in Firestore are not covered by the Encrypted workspace promise.
PC unlock. An unlocked phone can share the project key to the PC over an end-to-end grant (servers see opaque ciphertext). If the phone is offline, unlock once in the extension with your passphrase. Sync then uses the local device key.
Legacy plaintext until migration rewrite completes. Older projects and any Storage blobs not yet rewritten may still be plaintext and readable to Cepho operators with project access until those files are rewritten to ciphertext. After rewrite, at-rest Storage is ciphertext. Settings → Encrypt existing files rewrites leftover plaintext.
AI processing. Chat messages go to Anthropic's Claude API to produce replies. Anthropic is a sub-processor. Workspace files are not bulk-uploaded for chat. See anthropic.com/privacy.
Where a sub-processor is outside the EEA, we use Standard Contractual Clauses or equivalent safeguards.
Account and project data: kept while the account is active. After deletion we purge cloud data within 30 days unless law requires longer.
Beta data: until the beta ends or you ask us to delete it.
Waitlist data: until the waitlist closes or you ask to be removed.
Chat history: kept in Firestore until account deletion. Free tier limits monthly message quota, not how long history is stored.
You can access, rectify, erase, port, restrict, or object to processing of your personal data. Email support@cepho.cloud. We respond within 30 days.
You may also complain to Datatilsynet (Danish DPA): datatilsynet.dk.
Data controller: Cepho · support@cepho.cloud