Nexus-SecTech Ltd  ·  Android

CallVault

A personal Android call recorder. Records both sides of a call as separate channels, keeps them on your phone, and backs them up to your own Google Drive.

SHA-256
Hashed on write
drive.file
Only scope requested
Zero
Servers, accounts, analytics

Both sides, separately

Your voice and theirs are captured as distinct channels, so you can isolate either one — or listen to both together.

Verifiable

Every recording is stored with a SHA-256 hash and a sidecar describing the call. It is an audit tool, not a notes app.

Yours alone

No account, no server, no analytics. Backup goes to a folder in your own Drive using the narrowest scope Google offers.

How backup works

Backup is off until you choose a Google account. Once enabled, each recording and its sidecar are uploaded to a CallVault folder in that account's Drive, straight after the call rather than on a schedule — a phone lost an hour after an important call should not take the only copy with it.

The app requests a single OAuth scope, drive.file, which grants access only to files the app itself created. It cannot see anything else in your Drive. googleapis.com is the only internet destination it contacts.

The law on recording calls varies by country and sometimes by state. Making sure it is lawful where you are — and that anyone entitled to be told has been told — is the responsibility of whoever operates the device.

Availability

CallVault is a private tool, distributed directly and not published on Google Play. It requires Android 11 or later and depends on Shizuku to capture call audio.

Contact

hello@nexus-sec.tech