Privacy Policy

Who we are

Mdxt is developed by Uday Garg under the BlackBrain label (blackbrain.in), based in India. This policy applies to the Mdxt app on Android (Google Play, package in.blackbrain.mdxt), Windows, Linux, any future iOS / macOS builds on the Apple App Store, and the Mdxt website.

Questions? Email tigerhooduday@gmail.com.

What we collect: nothing

Mdxt contains no advertising SDKs, no analytics SDKs, no trackers, and no crash reporters. We never collect, receive, or transmit:

• Your notes, documents, file names, or anything you write.
• Your name, email, phone number, or any identity information.
• Your location, contacts, photos, or device identifiers.
• Usage analytics, telemetry, or behavioural data of any kind.

There is no BlackBrain account, no sign-up, and no backend. There is simply no server for your data to be sent to.

What stays on your device

Everything. Specifically:

• Your documents ordinary .md and .txt files in folders you choose, which you can open, back up, or delete with any file manager.
• App settings theme, language, and editor preferences.
• Sync tokens if you sign in with Google, the OAuth token lives in your device's secure storage and is used only to talk to your Drive.

Uninstalling the app removes its settings and tokens. Your note files remain wherever you saved them they're yours.

Google Sign-In and Drive sync (optional)

Mdxt works fully offline. Signing in with Google exists only to power sync, and is entirely optional.

When you enable sync, Mdxt creates a vault folder in your own Google Drive and syncs your notes directly between your devices and that folder over an encrypted (HTTPS) connection. Sign-in happens on Google's own screens Mdxt never sees your password. Your basic profile (name, email, photo) is shown in the app so you know which account is connected, and stays on your device.

The app requests only Google's most restrictive Drive permission, drive.file: it can see and modify only files it created itself, and nothing else in your Drive.

Mdxt's use of information received from Google APIs adheres to the Google API Services User Data Policy, including its Limited Use requirements. Google user data is used only to provide the sync feature, is never transferred to anyone, is never used for advertising, and is never used to train AI or machine-learning models.

You can revoke Mdxt's access at any time at myaccount.google.com/permissions.

Permissions

• Internet used only for the optional Drive sync. Without sign-in, the app makes no network requests of its own.
• File access to open and save your documents in folders you explicitly pick (on Android, via the system file picker).

Mdxt never requests your camera, microphone, location, contacts, or any other sensitive permission.

Third parties

The only third parties involved are ones you choose or that operate your platform: Google (Sign-In, Drive, and the Play Store) and Apple (for future App Store builds). Their handling of your data is governed by Google's and Apple's privacy policies. If the app crashes, Google Play or Apple may show us anonymised, aggregated crash statistics but only if you opted in to sharing diagnostics in your OS settings.

The Mdxt website is a static page: no cookies, no analytics, no ads.

Sharing and selling

We do not sell, share, rent, or trade personal information with anyone not advertisers, not data brokers, not "partners". We could not even if we wanted to: we don't have your data.

Deleting your data

You hold all the data, so deletion is entirely in your hands:

1. On your device uninstall Mdxt, and delete your note files if you no longer want them.
2. In your Drive delete the Mdxt vault folder at drive.google.com and empty the trash.
3. In your Google Account remove Mdxt's access at myaccount.google.com/permissions.

After that, no Mdxt-related data about you exists anywhere and none ever existed with us.

Security

All sync traffic is encrypted in transit (TLS). OAuth tokens are kept in your platform's secure storage and scoped to the minimal drive.file permission. Synced copies are protected by Google Drive's encryption at rest; local files by your device's own security. And with no servers, there is no server to breach. Found a vulnerability? Please write to tigerhooduday@gmail.com.

Children

Mdxt is a general-audience tool, not directed at children under 13. Because the app collects no personal data from anyone, it does not and cannot knowingly collect personal information from children. Google Sign-In is subject to Google's own age requirements.

Your rights

Privacy laws such as the GDPR (EU/UK), India's DPDP Act 2023, and the CCPA/CPRA (California) grant you rights to access, correct, delete, and port your personal data. Because we hold no personal data about you, these rights are satisfied by design: your notes are already in your possession as portable plain-text files, and there is nothing on our side to access or erase. We have not sold or shared personal information, ever.

To exercise any right or ask anything at all, email tigerhooduday@gmail.com. You may also complain to your local data-protection authority, though we'd appreciate the chance to help first. We will never discriminate against you for exercising a privacy right.

Store privacy labels

Our Google Play Data safety declaration: no data collected, no data shared; optional sync traffic is encrypted in transit; deletion is fully user-controlled. Syncing to your own Drive at your instruction is user-initiated storage, not developer collection. For future Apple builds, the App Privacy label is "Data Not Collected."

Changes to this policy

If Mdxt ever changes in a way that affects privacy, we will update this policy before the change ships, update the date at the top, and say so plainly in the release notes. The current version always lives at apps.blackbrain.in/Mdxt/privacy.html.

Contact

Uday Garg · BlackBrain, India
tigerhooduday@gmail.com · udaygarg.com · blackbrain.in