Sync for Proton

Sync for Proton syncs your Proton Contacts and Proton Calendar into Android's native contacts & calendar, so they work everywhere on your phone — the dialer, lock screen, smartwatch, and any calendar or contacts app. No Google account required.

This repository hosts signed APK releases for installing outside the Google Play Store (e.g. on GrapheneOS or any de-Googled Android). The app source is maintained privately; this repo contains downloads only.

⬇ Download the latest APK — a permanent link that always points to the newest release.

Requirements

• Android 10 (API 29) or newer
• A Proton account
• A subscription — 7-day free trial, then €2.39 / month or €23.99 / year (see Subscribing below)

Install with Obtainium (recommended)

Obtainium installs and auto-updates apps straight from GitHub releases. With Obtainium already installed, tap the button to add this app in one step:

Or add it manually:

1. Install Obtainium.
2. Tap Add App and paste this repo URL: https://github.com/bolausson/sync-for-proton
3. Obtainium finds the latest release APK — tap Install.
4. Future updates show up in Obtainium automatically.

Install from Uptodown

Also available on Uptodown, which can keep the app updated via the Uptodown app:

Install manually

1. Download the latest .apk from the Releases page.
2. Open it on your device and allow installing from this source if prompted.

Subscribing / activating

This build is paid via the web (no Google Play Billing):

1. Subscribe at https://apps.olausson.de/sync_provider_for_proton/checkout.html (monthly or yearly; 7-day free trial).
2. After payment, the page shows your subscription ID (starts with sub_). Copy it.
3. In the app: Settings → Subscription → Subscribe / Manage, paste the ID, tap Activate.
4. Keep the subscription ID somewhere safe (a password manager) — you'll need it to re-activate after reinstalling or on another device.

Manage or cancel anytime via the link in your Paddle receipt email.

Updates & signing

APKs are signed with a stable key; Obtainium recognises updates by signature. This build uses a different signing key than the Google Play version, so you can't switch between the two without uninstalling first.

Links

• Website: https://apps.olausson.de
• Privacy policy: https://apps.olausson.de/privacy-policy.txt