Sync without Google.
For GrapheneOS · source is live · not affiliated with Proton AG
Sync Proton contacts to GrapheneOS. Push and pull through the stock contacts app so the book lives in Proton, not only on the phone.
Built for phones that left Google.
GrapheneOS does not offer a Google account to hold your address book. AlpenSync is a simple way to sync Proton contacts to GrapheneOS so the stock dialer, messengers, and contacts app just work.
No Play Services. No FCM. No second inbox. The app is the pipe between Proton Mail contacts and Android’s native contacts. LineageOS and similar de-Googled Android are also in scope.
Contacts now. Calendar next.
Two-way Proton contact sync: pull the book onto the phone, and push local creates, edits, and deletes back to Proton. Add someone in the native contacts app and they can land in Proton Mail. Change a number on the web and the next sync brings it down.
Contacts are written into Android’s system providers, so they behave like any other native contact. On-device cryptography unlocks Proton’s encrypted vCards on the handset. The app is a client, never a relay. Calendar sync and mail notifications are later; they will use the same core, still without Google.
Lose the phone. Keep the contacts.
A GrapheneOS install is easy to wipe and easy to replace. Native contacts that live only on the device die with it. AlpenSync keeps the durable copy in Proton: push from the phone, pull onto the next one.
Flash a new build, lose the handset, or factory-reset. Sign in to Proton again and sync Proton contacts back to GrapheneOS. The stock contacts app fills. The dialer knows the numbers. Nothing here depends on Google backup.
- 01 Sign in on the device
Proton account, on-device key unlock. Traffic only to Proton hosts.
- 02 Pull into Android
Contacts land in the system provider. The stock apps see them.
- 03 Push changes back
Edits on the phone write to Proton. The book outlives the hardware.
Read this before you trust it.
Uses Proton’s undocumented, unofficial API. Sync may break without notice.
Contacts live decrypted in Android’s system providers. That is how the dialer sees them.
No telemetry. Traffic only to Proton hosts, enforceable and auditable in source.
Independent community project. Not affiliated with, endorsed by, or supported by Proton AG.
Questions people actually ask
Short answers for “sync Proton contacts to Graphene,” two-way push and pull, and what survives a wipe.
How do I sync Proton contacts to GrapheneOS?
AlpenSync is an Android sync client for Proton Mail contacts on GrapheneOS. Sign in to Proton, unlock keys on the device, and the app writes contacts into Android’s system Contacts provider. The stock dialer and contacts app see them like any other native contact. No Google account and no Play Services.
Is Proton contact sync two-way (push and pull)?
Yes. Pull brings Proton contacts onto the phone. Push writes local creates, edits, and deletes back to Proton as encrypted contacts. Change a number in the native contacts app and it can go back to Proton. Change it in Proton Mail and the next sync brings it down.
What happens if I wipe GrapheneOS or lose the phone?
The durable copy is Proton, not the handset. If the phone is lost, stolen, or wiped, the contacts are still in the Proton account. Set up GrapheneOS again, sign in to AlpenSync, and pull the book back into the stock contacts app. That is the point of two-way sync on a de-Googled phone: native contacts without depending on the device to survive.
Does this need Google Play Services or a Google account?
No. AlpenSync is built for GrapheneOS and similar de-Googled Android (including LineageOS). It uses Android’s built-in sync framework and WorkManager. There is no Firebase, no FCM, and no Google backup of the address book.
Where do contacts live, and is cryptography on-device?
Proton stores contacts as encrypted vCards. AlpenSync decrypts them on the device and writes the result into Android’s Contacts provider so the dialer can use them. That means contacts are decrypted on the phone while they are in the system provider, the same exposure as any contacts sync app. Cryptography stays on-device; the app is a client, never a relay.
Is AlpenSync affiliated with Proton or GrapheneOS? Is it finished?
AlpenSync is an independent GPL-3.0 project. It is not affiliated with, endorsed by, or supported by Proton AG or the GrapheneOS project. It uses Proton’s undocumented, unofficial API, so sync may break when Proton changes something. The project is in development; the source is the product.
The source is the product.
GPL-3.0. In development. The trust mechanism is the repository, not a store listing.
View sourceThreat model in the repository
Licensed GPL-3.0