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ex-Cloud · Tutorial 6 of 6

Privacy, security and data flow

This app touches some of your most personal data: contacts and appointments. Here is exactly where each piece of data goes.

About 3 minutes

Data flow at a glance

Data	Where it goes	When
Account password	This phone only (Android Keystore encryption)	When you add an account
Contacts / calendar	Your DAV server ⇄ local database	On refresh (download only)
Phone copies	The phone's address book / calendar	When you tap Download to phone
Merge result	Back to your DAV server	When you confirm a merge
AI cleanup content	The AI service you configure (optional)	When you run an AI task

1One-way is a safety feature

Nothing you change on the phone is pushed back to the cloud. That means:

Someone messing with the phone's contacts cannot pollute your iCloud.
Changing the cloud is possible only through Merge or AI cleanup, both of which ask first.

The trade-off: contacts added on the phone will not appear in iCloud. That is deliberate.

Duplicates — The only place that deletes cloud data — with a second confirmation

2How the password is stored

Encrypted with a key held by the Android Keystore, then written to the local database.
Copying the database off the device does not reveal it — the key never leaves the device.
Removing the account deletes the encrypted secret.

Use an app-specific password rather than your main Apple ID password: it can be revoked separately.

Accounts — Each account can be removed independently

3AI is optional

Without an AI configuration the app works fully: browsing, downloading, verifying, merging and exporting.

Content is sent to your chosen service only when you run an AI task.
The API key is encrypted with the Keystore as well.
Deterministic rules (removing sorting prefixes, etc.) run entirely on the device.

The AI service lives under Settings → Assistant

4Clearing your data

Phone copies → bin icon: delete the copy written into the phone.
Accounts → remove: drop the account and its encrypted secret.
System settings → Apps → ex-Cloud → Storage → Clear data.

All three only affect this phone and this app. They do not delete anything in your cloud (except a deletion you explicitly confirmed during a merge).

Phone copies — Deleting a copy only touches the phone