UROP Proceedings 2020-21

School of Engineering Department of Computer Science and Engineering 105 Decentralized Mobile Applications Supervisor: CHATZOPOULOS Dimitrios / CSE Student: CHONG Cheuk Hei / COMP Course: UROP1100, Fall This research project has been involved in developing simple decentralized mobile applications built with Flutter, a cross-platform mobile frontend framework, to interact with smart contracts powered by Solidity programming language in the Ethereum test network, which simulates depositing and withdrawal function in DeFi applications. Decentralized Mobile Applications Supervisor: CHATZOPOULOS Dimitrios / CSE Student: EDRIC Jovan / COMP Course: UROP1100, Fall Mobile Applications have long relied on conventional centralized servers for storing and processing data. As concerns over centralization have risen and the need for decentralization has increased, blockchain technology seems poised to replace the backend infrastructure of traditional centralized applications. The convenience of centralized servers, however, is still a major selling point for most developers. The proposed semi-decentralized application offers a platform in which users can offer freelance service to potential clients of the app. It adopts the Ethereum blockchain for securing transactions and user authentications, while employing an online centralized database, for storing additional data, including user and service information, benefiting from the convenience of a centralized server and security of a blockchain. Decentralized Mobile Applications Supervisor: CHATZOPOULOS Dimitrios / CSE Student: MA Jianheng / RMBI Course: UROP1100, Fall One of the prevalent applications of using blockchains nowadays is smart contract. Solidity is an high-level and object-oriented language to implement smart contracts. It was developed based on C++, Python and JavaScript, and is designed to aim at the Ethereum Virtual Machine (EVM). To enable users to easily interact with the smart contracts, web3.js is used to developed frontend application. This reports uses both remix and Ethereum Studio to demonstrate several examples.