Terms of Use for the Monitor KSeF Application

1. General provisions

1.1. These Terms of Use govern the use of the Monitor KSeF mobile application (hereinafter: the "Application") available for iOS, published by KrzewiLabs, based in Poland (hereinafter: the "Publisher").

1.2. The Application enables entrepreneurs to browse structured invoices from the National e-Invoicing System (KSeF) operated by the Ministry of Finance of the Republic of Poland. The Application acts as a read-only client accessing the official KSeF API — it is not part of the KSeF system, is not a product of the public administration, and is not affiliated with the Ministry of Finance or the National Revenue Administration (KAS).

1.3. Downloading, installing or using the Application constitutes acceptance of these Terms in their entirety. If the User does not accept these Terms, the User should discontinue use of the Application and uninstall it.

1.4. These Terms are available within the Application under the Info tab and on the website at https://monitorksef.pl/regulamin_ios.html.

2. Definitions

Whenever these Terms refer to:

• Application — the Monitor KSeF mobile application for iOS, published by the Publisher.
• Publisher — KrzewiLabs, the entity responsible for the development and maintenance of the Application; contact: kontakt@krzewilabs.pl.
• User — a natural person who has installed the Application on their device and uses it in accordance with these Terms.
• KSeF — the National e-Invoicing System (Krajowy System e-Faktur) operated by the Ministry of Finance of the Republic of Poland, enabling the issuance, receipt and storage of structured invoices.
• KSeF API — the programmatic interface for accessing the KSeF system provided by the Ministry of Finance at api.ksef.mf.gov.pl.
• NIP — the Polish Tax Identification Number (Numer Identyfikacji Podatkowej), a 10-digit number identifying a taxpayer in Poland.
• KSeF Token — an authorisation string issued by the Ministry of Finance, granting authentication access to the KSeF API.
• Structured invoice — an invoice in XML format conforming to the FA(3) schema of KSeF, constituting a legal document under Polish VAT legislation.
• Plus Subscription — a paid subscription (In-App Purchase) unlocking additional Application features, processed through the Apple App Store.
• PDF Visualisation — a PDF file generated by the Application presenting a graphical representation of structured invoice data, intended solely for informational and private archival purposes.
• Device — an iPhone or other Apple device running iOS on which the Application is installed.

3. Technical requirements

3.1. Use of the Application requires:

• a device running iOS at the version indicated on the Application's App Store page (currently iOS 17.0 or later),
• an active internet connection (Wi-Fi or cellular data) to communicate with the KSeF API,
• possession of a NIP and an active KSeF token with invoice read permissions (issued by the Ministry of Finance).

3.2. The Publisher shall not be liable for inability to use the Application resulting from unmet technical requirements, internet connectivity issues, or unavailability of the KSeF system on the Ministry of Finance's side.

4. Configuration and use of the Application

4.1. The Application does not require creating a user account. Configuration consists of:

• setting a PIN code to secure access to the Application,
• entering a NIP and KSeF token in the Configuration tab.

4.2. The User is solely responsible for the confidentiality and security of their PIN code and KSeF token. The Publisher has no access to this data and cannot recover it.

4.3. In case of a lost PIN code, the only solution is to uninstall and reinstall the Application, which results in the loss of all data stored locally on the device.

4.4. The User may optionally enable biometric authentication (Face ID, Touch ID or Optic ID) as an alternative to the PIN code. Biometric processing is handled exclusively by iOS — the Application does not process or store biometric data.

5. Scope of Application functionality

5.1. The free version of the Application provides:

• browsing the list of structured invoices associated with the User's NIP,
• filtering invoices by date range, entity type (seller, buyer) and date type,
• automatic checking for new invoices from the current day when the Application is launched.

5.2. The Plus version (after purchasing a Plus Subscription) additionally provides:

• viewing invoice details (transaction parties, line items, VAT amounts),
• exporting an invoice visualisation to a PDF file,
• downloading the original XML invoice file in FA(3) format from the KSeF system,
• viewing the XML code of an invoice directly within the Application.

5.3. The Application communicates exclusively with the official Ministry of Finance API (api.ksef.mf.gov.pl). The Publisher does not operate its own servers that process User data.

5.4. The Publisher reserves the right to modify the scope of Application features, including adding new features or changing the assignment of features between the free and Plus versions, of which Users will be notified via a message within the Application or through an App Store update.

6. Monitor KSeF Plus subscription

6.1. The Plus Subscription is a paid service processed exclusively through the Apple App Store In-App Purchase mechanism. The Publisher does not process or store the User's payment data — payment is handled entirely by Apple.

6.2. The Plus Subscription renews automatically. The fee for the next billing period is charged by Apple 24 hours before the renewal date. The current subscription price is displayed on the purchase screen within the Application and in the App Store.

6.3. The User may cancel the subscription or manage its renewal at any time via:

• the Application: Info → Monitor KSeF Plus → Manage subscription,
• iOS settings: Settings → [user name] → Subscriptions → Monitor KSeF Plus.

6.4. After cancellation, access to Plus features remains active until the end of the current billing period.

6.5. If a refund is granted by Apple, the Application will automatically deactivate access to Plus features.

6.6. After changing devices or reinstalling the Application, the User may restore a previously purchased subscription using the Restore Purchases function — Apple will verify the previous purchase linked to the User's Apple ID.

6.7. In-App Purchase rules, including the right of withdrawal and refund, are governed by the Apple Media Services Terms and Conditions. The User acknowledges that the Publisher is not a party to the payment transaction and cannot issue refunds independently — refund requests should be directed to Apple.

7. PDF invoice visualisation

7.1. The Application enables the generation of a PDF visualisation of an invoice based on data retrieved from the KSeF system. The PDF visualisation is intended solely for informational purposes and the User's private archival use.

7.2. The PDF visualisation may not be treated as:

• an original or copy of an invoice within the meaning of tax legislation,
• a basis for pursuing claims,
• a document confirming a transaction within the meaning of law,
• a substitute for a structured invoice in XML format.

7.3. The Publisher makes reasonable efforts to ensure that the PDF visualisation faithfully reflects the data contained in the XML invoice retrieved from KSeF; however, it does not guarantee full consistency between the visualisation and the original XML in every case. In the event of any discrepancy between the PDF visualisation and the XML file, the XML file of the structured invoice stored in the KSeF system shall prevail.

7.4. The User uses the PDF visualisation at their own risk and acknowledges that the Publisher shall not be liable for any consequences of using the PDF visualisation as a legal document or a basis for claims.

7.5. PDF files are generated temporarily in the device's temporary directory and are automatically deleted after sharing is complete. The Application does not permanently store PDF files.

8. User obligations and liability

8.1. The User undertakes to:

• use the Application in accordance with its intended purpose, these Terms and applicable law,
• protect the confidentiality of their PIN code and KSeF token from third-party access,
• use the Application only on devices to which they have lawful access,
• refrain from attempting reverse engineering, decompilation, disassembly or any interference with the Application's source code,
• refrain from circumventing the Application's security mechanisms.

8.2. The User bears full responsibility for:

• the accuracy of the configuration data entered (NIP, KSeF token),
• all actions performed in the Application using their PIN code or biometric data,
• decisions made on the basis of data displayed by the Application,
• sharing exported PDF files, XML files and diagnostic logs with third parties.

8.3. The Application is intended exclusively for adult users (at least 18 years of age) who conduct business activity or act on behalf of entities authorised to use the KSeF system.

9. Limitation of the Publisher's liability

9.1. The Application is provided "as is." The Publisher exercises due diligence to ensure the proper functioning of the Application but does not guarantee its uninterrupted and error-free operation.

9.2. The Publisher shall not be liable for:

• the operation, availability or correctness of the Ministry of Finance's KSeF system,
• the content, accuracy or completeness of invoices retrieved from the KSeF system — the Ministry of Finance, as the system administrator, is responsible for data in the KSeF system,
• damages resulting from treating a PDF visualisation as a legal document or a basis for claims (see section 7),
• loss of data resulting from uninstalling the Application, device damage or User actions,
• interruptions in the Application's operation caused by iOS updates, changes to the KSeF API or factors beyond the Publisher's control,
• consequences of unauthorized access to the User's device,
• business, tax or legal decisions made on the basis of data displayed by the Application.

9.3. To the maximum extent permitted by applicable law, the Publisher's total liability to the User in connection with the use of the Application is limited to the amount paid by the User for the Plus Subscription during the 12 months preceding the event giving rise to the claim.

9.4. The above limitations of liability do not exclude or limit the Publisher's liability to the extent that such exclusion or limitation is impermissible under mandatory provisions of Polish or EU law, in particular consumer protection legislation.

10. Data security

10.1. The Publisher applies the following technical measures to protect User data:

• NIP, KSeF token and PIN hash are stored exclusively in the encrypted iOS Keychain with an attribute preventing access after restoring a backup on another device,
• the PIN is secured using the PBKDF2-HMAC-SHA256 algorithm with 100,000 iterations and a random 32-byte salt,
• all connections to the KSeF API are encrypted (TLS 1.2+) and protected by certificate pinning,
• invoice data is stored exclusively in RAM and is erased when the Application is closed,
• the Application automatically locks when entering the background and masks screen content in the multitasking view,
• diagnostic logs are automatically redacted — tokens, NIPs and other sensitive data are removed.

10.2. The Application does not send any data to the Publisher's servers. The only external server the Application communicates with is the official Ministry of Finance server (api.ksef.mf.gov.pl) and Apple infrastructure (App Store, StoreKit).

10.3. The Application does not contain any tracking tools, behavioural analytics, advertisements or third-party data-collecting SDKs.

10.4. Despite the above measures, the Publisher notes that no security system provides absolute protection, particularly in the event of physical access by an unauthorised person to an unlocked device.

11. Personal data protection

11.1. The controller of personal data processed locally on the device in connection with the use of the Application is the Publisher (KrzewiLabs).

11.2. Detailed rules on personal data processing, including the scope of data collected, purposes and legal bases of processing, User rights under the GDPR and information about data recipients, are set out in the separate Privacy Policy available:

• in the Application: Info → Privacy Policy,
• on the website: privacy-policy.html.

11.3. The controller of data processed within the KSeF system is the Ministry of Finance of the Republic of Poland. The rules governing data processing by the Ministry of Finance are set out in its own privacy policy available at podatki.gov.pl.

12. Intellectual property

12.1. The Application, including its source code, graphical interface, icons, visual elements, names and logotypes, constitutes the intellectual property of the Publisher and is protected under copyright and industrial property law.

12.2. The User is granted a non-exclusive, non-transferable, revocable licence to use the Application in accordance with its intended purpose and these Terms. The licence covers only the right to use the Application on the User's devices.

12.3. The User may not copy, modify, distribute, decompile, disassemble or create derivative works based on the Application, unless permitted by mandatory provisions of law.

12.4. The names "KSeF" and "Krajowy System e-Faktur" are the property of the Ministry of Finance of the Republic of Poland. The use of these names in the Application is for informational purposes and does not imply any affiliation with the Ministry of Finance.

13. Complaints

13.1. The User has the right to submit complaints regarding the operation of the Application. Complaints should be sent to: kontakt@krzewilabs.pl.

13.2. A complaint should include:

• a description of the problem and the circumstances of its occurrence,
• the Application version and iOS version (available in the Info tab),
• the expected resolution.

13.3. The Publisher shall review the complaint and respond within 14 days of receipt. In justified cases, the deadline may be extended to 30 days, of which the User will be notified.

13.4. Complaints concerning payments for the Plus Subscription, including refund requests, should be directed to Apple in accordance with the Apple App Store terms, as the Publisher is not a party to the payment transaction.

13.5. A User who is a consumer has the right to use out-of-court complaint resolution and redress mechanisms, including the ODR (Online Dispute Resolution) platform available at: https://ec.europa.eu/consumers/odr/.

14. Amendments to these Terms

14.1. The Publisher reserves the right to amend these Terms for important reasons, in particular in the event of:

• changes in legislation affecting the rules of use of the Application,
• changes in the Application's functionality,
• changes in the operation of the KSeF system,
• changes required by the Apple App Store.

14.2. Users will be notified of material changes to these Terms by:

• a message displayed in the Application after launch,
• an update to the "Last updated" date in this document.

14.3. Continued use of the Application after the publication of amended Terms constitutes acceptance of the new conditions. If the User does not accept the changes, the User should discontinue use of the Application and uninstall it.

15. Final provisions

15.1. These Terms are governed by Polish law. Matters not regulated herein shall be governed by the provisions of Polish law, in particular the Civil Code, the Consumer Rights Act, the Act on the Provision of Electronic Services and the GDPR.

15.2. Any disputes arising from the use of the Application that cannot be resolved amicably shall be settled by the court having jurisdiction under applicable law. For Users who are consumers, the competent court is the court of the consumer's place of residence.

15.3. If any provision of these Terms is found to be invalid or unenforceable, the remaining provisions shall remain in force. The invalid provision shall be replaced by one closest to its economic purpose to the extent permitted by law.

15.4. These Terms enter into force on 02.03.2026.

Contact the Publisher:
KrzewiLabs
E-mail: kontakt@krzewilabs.pl
Website: https://www.krzewilabs.pl/

© 2026 KrzewiLabs. All rights reserved.