Secure data sharing: e-receipts for PayD

Multifunctional mobile apps for managing digital receipts on iOS and Android


PayD, a Polish startup specialising in secure customer data sharing, developed encrypted storage for transactions before the e-receipts launch in Poland. Their Fast Forward Data Privacy Protocol (DPP) retrieves historical customer data, offering transaction history pre-e-receipts for individual customers and retailers. With PayD's tech, retailers can implement e-receipts, avoid printing for offline/cash transactions, and create payment card-based loyalty programs. The use of high-grade cryptography, including blockchain and advanced identity encryption, ensures privacy and transparency in data processing. Having completed backend work, PayD sought frontend specialists to design and develop mobile apps compatible with iOS and Android. That's when the collaboration with Happy Team began.








18 months

Scope of work

Software development, UX/UI design

Team involved

UX/UI designer, React developers, .NET developers, project manager


React, .NET, Azure

Business needs and goals


The project's core objective was to develop user-friendly mobile apps for Android and iOS. These apps aimed to store digital receipts, enhance return processes, and collect data for reports and analysis.

The detailed aims of the project included the design and development of:

  • A white-label Personal Finance Management mobile application for collecting receipts, facilitating returns with cryptographic proof of purchase, and analysing financial data.
  • A QR code scanner and displayer.
  • A mobile app tailored for retailers, allowing audits on their digital receipt data usage, tracking who accessed it, when, and how.

Our role

Happy Team’s role:

  • Defining the project scope and selecting essential functionalities for both applications.
  • Adapting the applications to meet formal requirements.
  • Conducting workshops with stakeholders to refine UX and UI designs, prioritising and crafting functionalities and elements for both applications.
  • Application development.
  • Thorough testing phases.
  • Deploying the applications and making necessary adjustments.


Happy Team designed and developed two mobile applications, both for iOS and Android, that include:

  • Multiple registration and login methods.
  • Client consent management.
  • Display of digital receipts with itemised details.
  • A QR code scanner and displayer.
  • Integration with the company's cloud system.
  • Integration with the Polish Ministry of Finance digital receipt system.
  • Reports with filtering and sorting options (by category, time, cost, etc.).
  • Payment module.

PayD expanded its offer by introducing a well-designed white-label mobile application for individual customers and a fully functional app for retailers. This move enhanced the startup’s attractiveness to clients by providing comprehensive solutions in the emerging field of e-receipts.

For more information check our client's website:

"We strongly recommend cooperating with Happy Team for startups that require a flexible and dynamic approach."

Łukasz Wiśniewski, CEO of PayD

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