Summary
Last updated: November 4, 2026
Invoice Track is a desktop application that downloads electronic invoices (PDF and XML) from your Gmail messages and organizes them on your computer. Everything is processed locally: we do not send your emails, attachments or credentials to any server operated by the developer or to any third party, we do not sell data, and we show no advertising.
Invoice Track's use and transfer to any other app of information received from Google APIs will adhere to the Google API Services User Data Policy, including the Limited Use requirements.
1. Who is responsible
Invoice Track is developed and maintained by Nolan Calderón, who is responsible for all interaction with users and for the development of the application. To contact the developer, get in touch with Nolan Calderón at nocalde28@gmail.com, for any question about this policy or your data.
2. Google user data the app uses
When you authorize an account with Google Sign-In, Invoice Track requests a single scope: https://www.googleapis.com/auth/gmail.modify. It is used only for the following:
| Google data | Purpose |
|---|---|
| Email address of the authorized account | Identify the client's account and open the right message in Gmail. |
| List of matching messages (identifier, received date, labels, attachment names and types) | Find the emails that carry an invoice (one PDF and one XML) in the chosen date range, and avoid repeating those already processed. |
| PDF and XML attachments of those messages | Download them, classify them as purchase or sale, and save them on your computer. |
| Gmail labels | Create, if missing, and apply the Procesado ("Processed") label to messages already saved. |
To locate attachments, Gmail returns the full message to the app, but Invoice Track does not store or display the body of your emails; it keeps only the data in the table above. The app never deletes or sends email and does not alter message content; the only change it makes in Gmail is the Procesado label.
3. What is stored and where
Everything is stored on the computer where the app is installed:
- Downloaded invoices (PDF and XML): in the folder you choose. Next to each one, a hidden file keeps the Gmail message identifier so that retries do not create duplicates.
- Access credentials (Google tokens): one file per account, in the app data folder of the operating-system user, with access restricted exclusively to the current operating-system user (0600 permissions on macOS and Linux and, on Windows, the file's access control list). Tokens are never written to the log or included in the application package.
- Client list: the name, Gmail address and tax ID you enter for each client, and the app settings (invoice folder, theme).
- Activity log: technical events used to diagnose errors, without tokens or secrets.
The app's interface is a local server that listens only on 127.0.0.1; it is not reachable from other machines.
Data stays on the computer where the app runs and is accessible to whoever uses that computer and the app (for example, an accountant who manages invoices for clients). Anyone who connects another person's account must have that account holder's consent.
4. Who the data is shared with
No one. Google user data is not transferred to the developer or to third parties; it is not sold; it is not used for advertising, profiling or list building; it is not used to train artificial-intelligence or machine-learning models; and no person reads it other than the user of the app on their own computer.
The app communicates over the Internet only with Google (OAuth sign-in and the Gmail API) to perform the actions described in section 2. In addition, the interface may load the Inter typeface from Google Fonts; that request contains no data from your account or emails.
Invoice Track's use and transfer to any other app of information received from Google APIs will adhere to the Google API Services User Data Policy, including the Limited Use requirements.
5. Security
- Authorization uses Google's OAuth 2.0 standard: the app never sees or stores your password.
- Configuration and token files are written atomically so they are not left corrupted.
- XML files are parsed safely (documents with DTDs or external entities, and oversized ones, are rejected).
- If Google revokes the authorization, the app reports it and asks you to authorize again; it does not retry in a loop.
6. Retention and deletion
- Revoke access at any time at myaccount.google.com/permissions. The app will no longer be able to read that account.
- Deleting a client in the app also deletes its access token from the computer.
- Uninstalling: the Windows uninstaller asks whether you also want to delete the saved settings and credentials; your invoices are never deleted automatically.
- Invoices and local data remain until you delete them; deleting the invoice folder and the app data folder is enough.
- The Procesado label in Gmail is not removed automatically; you can delete it from Gmail.
Because we do not store your data on our servers, there is no data of yours to request from the developer; if you have questions, write to nocalde28@gmail.com.
7. Children
Invoice Track is not directed to children and does not knowingly collect their data.
8. Changes to this policy
If this policy changes, the new version will be published at this same address with its update date. If a change materially affects how your Google data is used, your authorization will be requested again.
9. Contact
To contact the developer, get in touch with Nolan Calderón at nocalde28@gmail.com.