APHELION
Privacy Policy
Aphelion · Effective June 2026
Who we are
Aphelion is a zero-knowledge messaging app. This policy explains what the Aphelion app and its relay server handle and how.
No accounts
Aphelion does not ask for an email address, phone number or real name. Your identity is a cryptographic key pair (Ed25519 for signing, X25519 for encryption) generated on your device. The alias you choose is shared only with the people you message.
On-device storage
Your keys, contacts, chats and files are stored only on your device in a local SQLite database that is encrypted with AES-256-GCM using a key derived from your passphrase (PBKDF2-SHA256). We cannot recover your passphrase or your data.
What the relay sees
Messages are end-to-end encrypted on your device and sealed with a fresh ephemeral key for each recipient. The relay only receives the ciphertext, an ephemeral public key and a routing tag derived from the recipient's public key. It does not learn who sent a message, and never receives readable content, aliases or file names.
Retention
Encrypted messages are held on the relay only until the recipient's device acknowledges delivery, and then deleted. Undelivered messages and encrypted file blobs are deleted automatically after at most 7 days. Burn-on-read messages are destroyed on both devices when their timer ends after being read.
Decoy Vault
You can create a second vault opened by a different passphrase. Both vault slots always exist on the device and look identical, so nobody can tell whether a decoy exists.
Sharing
We do not sell or share data. The relay is hosted by our infrastructure provider and only holds encrypted payloads as described above.
Deleting your data
Use Panic Wipe (in Settings or on the unlock screen) to permanently destroy every vault on the device. Uninstalling the app or clearing site data also removes it. Nothing about you remains on our servers once pending deliveries are acknowledged or expire.
Children
Aphelion is not directed to children under 13.
Changes
We may update this policy; significant changes will be announced in the app. Last updated: June 2026.