*Proceeding Paper* **COVID-19 Digital Vaccination Passport Based on Blockchain with Its Own Cryptocurrency as a Reward and Mobile App for Its Use †**

**Mauro Alberto de los Santos Nodar 1,\* and Tiago Manuel Fernández Caramés 1,2,\***


**Abstract:** Due to the recent outbreak of the COVID-19 pandemic, everybody's lives have changed dramatically and society went through new stages accompanied by new needs. This article details a solution for one of these needs, since it provides a system of digital certificates for the secure storage and sharing of medical data related to COVID-19, with the goal of demonstrating immunity or lack of viral infection in a unequivocal, unbreakable and secure way. The proposed system is based on Blockchain and its inherent benefits, developing also a decentralized, mobile and multiplatform app for its use and an incentive system with a customized cryptocurrency in order to reward the users who use it.

**Keywords:** blockchain; smart contract; Ethereum; cryptocurrency; COVID-19; digital vaccination passport; immunity certificate; distributed mobile application; kotlin mobile multiplatform
