Download the "taxx.lu Scanner" app from the App Store or Play Store. Using the application, scan the QR code found in the "Auto Scan" form of your tax return on taxx.  You then have several possibilities to add your documents:  By taking a photo directly with the application By choosing a file in your smartphone By choosing a document from a third-party application The documents will be automatically added to taxx.lu and you will be able to see the details in the "Auto Scan" form.  3 possible cases:  Complete import : The data of your document has been correctly imported.  Incomplete import: Some data could not be imported. You will have to fill in the missing data in the following forms.  Import not possible: The data of your document could not be imported. You will have to add the document in the appropriate category.