Card Scanner

Organisations that issue physical cards to staff or drivers often need an inventory: which card went to whom, and when. Doing this with a notes app or a spreadsheet means someone types card numbers by hand, which is slow and puts full card numbers into files that then get emailed around. It is the kind of quiet data-protection problem that nobody owns until an audit finds it.

An offline Android application that scans a card with the camera, keeps only the masked number and the last four digits, and exports an Excel workbook. The privacy guarantees are structural rather than procedural: there is no column that can hold a full card number, the application declares no network permission at all, card images are captured in memory and discarded, and the exporter re-scans its own finished workbook and rejects it if any card-number-like sequence appears.

• Camera scanning with a fast capture interface
• Masked-number-only records: the data model exposes a masked number and last four digits, with no field able to store a full number
• No CVV, PIN, magnetic-stripe or chip data is read or stored — there is no recognition path and no column for it
• On-device optical character recognition with the bundled offline model
• Formatted Excel workbook export, matching the layout of the issuing organisation’s own tracking sheet
• Export self-verification: the finished workbook is re-scanned and rejected if a card-number-like sequence is found
• Sensitive fields cleared from memory once consumed
• No network permission declared, so the application is technically unable to transmit data
• Screen-capture protection and cloud-backup exclusion
• Six published releases with downloadable builds

• It records card inventory only. It is not a payment terminal and cannot authorise, charge or process a payment.
• It is not affiliated with, endorsed by or sponsored by any card network; “Visa” appears only in the repository name because that is the card type it was written for.
• No automated test suite and no CI workflow.
• No licence file is published.
• The project is recent, so it has not been proven at scale.
• It handles payment-card data by nature, so no screenshot can be published — every visual here is an illustration.

• Kotlin
• Android
• ML Kit
• Gradle
• Excel export