English
Privacy Policy
App: Envelopes: My Budget (Android) Developer: Ivanov Oleg Contact: support@envelopesbudget.org Effective date: 11 September 2026
In short
The app has no server of its own. Your financial data is stored on your device and, if you choose to enable it, in your own cloud storage. The developer does not receive, store or process this data and has no technical means of seeing it.
The app contains no advertising, uses no analytics, and shares no data with third parties for marketing.
What data the app handles
Everything you enter yourself: accounts, transactions, amounts, categories, payees, notes, scheduled payments, goals and - if you wish - photos of receipts. This information is kept in a database on your device.
The app does not request or collect your name, address, phone number, contacts, list of installed apps, advertising identifiers or location data.
Where the data is stored
On your device. The primary storage is a database in the app’s protected area. Uninstalling the app removes this data with it.
In your cloud - only if you connect it yourself. The app can synchronise your budget and store backups in one of these services: Google Drive, Dropbox or a WebDAV server. Data travels directly between your device and your own account in that service. The developer is not part of this chain and has no access to the files.
For Google Drive the app uses restricted access (drive.file): it can only
see the files it created itself and cannot browse the rest of your drive. In
Dropbox the app works inside its own folder and has no access to other files.
Over your local network. There is a mode for transferring data directly between two of your own devices over Wi-Fi. The data goes directly, bypassing the internet and any servers, and is encrypted with a one-time confirmation code that you enter manually.
Encryption
If you set a password (the Backups section in the app), it encrypts everything that goes to your cloud: backups, receipt photos and the budget sync file. The cipher is AES-GCM with a 256-bit key derived from the password via PBKDF2.
The password is kept only on your device in the Android secure storage and is never transmitted - neither to the developer nor to the cloud. If you forget this password, the files cannot be decrypted - neither by you nor by the developer.
Without a password these files sit in your cloud in the clear. The sync file is compressed (plain gzip) - that saves mobile traffic and is not a security measure.
The encrypted file format is open
Your data should not depend on a single program, so the format is described here. Knowing it does not weaken anything: the strength rests on the password, not on the secrecy of the format.
The file starts with the four bytes MB2E, followed by a 16-byte salt, a
12-byte nonce, the ciphertext and a 16-byte GCM tag. The key is
PBKDF2-HMAC-SHA256, 600,000 iterations, 256 bits; the cipher is AES-GCM-256.
Given the password, such a file can be decrypted by any tool that supports
these standard algorithms. Files starting with MB1E are the same format
from an earlier version with 100,000 iterations; the app still reads them.
A decrypted sync file may turn out to be gzip - any archiver unpacks it, and inside there is ordinary JSON.
The app does all of this for you: Backups → the ⋮ menu → “Save a readable copy”. It strips both the encryption and the compression and gives you a plain file that anything can open.
Wi-Fi transfers between devices are encrypted as well; the key is derived from the six-digit confirmation code, and the code itself is never sent over the network.
Permissions and why they are needed
| Permission | Purpose |
|---|---|
| Internet | synchronisation with the cloud storage you connected |
| Camera | photos of receipts and QR code scanning |
| Microphone | voice entry of a transaction (recognition is done by Android) |
| File access | saving and reading backups, import and export |
| Biometrics | unlocking the app with a fingerprint or face |
| Notifications | reminders about scheduled payments |
| Local network | direct transfer between your own devices over Wi-Fi |
The app does not request location permission.
Voice entry uses the Android system speech recognition service. The spoken phrase is processed by the operating system and is subject to the privacy policy of that system’s provider.
Third-party services
The app contacts only the services you connect yourself:
- Google Drive - Google Privacy Policy
- Dropbox - Dropbox Privacy Policy
- WebDAV - the server you specify; its terms are set by its owner
None of these services receive data from the developer - only from you and at your initiative.
Payments
If paid features appear in the app, payments will be processed through Google Play. Payment details are handled by Google and are not passed to the developer. The developer receives from Google Play only the purchase status needed to grant access.
Children
The app is not directed to children under 13 and does not knowingly collect data from them.
Your rights and data deletion
The data is yours and stays under your control:
- to delete data from the device - uninstall the app or use the reset option in settings;
- to delete data from the cloud - remove the app’s folder in your Google Drive, Dropbox or on your WebDAV server;
- to take your data with you - the app can export a backup as a file, export transactions to CSV, and turn an encrypted or compressed cloud file into a plain one (“Save a readable copy”, see the Encryption section).
There is no need to send a deletion request to the developer: the developer does not hold your data.
Error log
The app keeps a technical log of synchronisation events and errors. The log is stored on the device only, is never sent anywhere automatically, and is visible to you in settings. If you decide to send it to help resolve an issue, that happens solely through your explicit action.
Changes to this policy
The current version of this document is always available at https://envelopesbudget.org/privacy-en/. If the policy changes materially, the effective date will be updated.
Contact
Privacy questions: support@envelopesbudget.org