UROP Proceedings 2020-21

School of Engineering Department of Computer Science and Engineering 106 Decentralized Mobile Applications Supervisor: CHATZOPOULOS Dimitrios / CSE Student: RUBAB Tamzid Morshed / DSCT Course: UROP1100, Fall This article is a progress report of my project on decentralized android application. The application is an online two player Tic-tac-toe game. Its back-end is implemented with Solidity programming language and front-end is under development with XML, Java, and Web3j in android studio. It supports creating and managing accounts for each player, creating a game and password protecting it, joining a game created by a friend or stranger, taking turn in the game, and saving the statistics after the game ends. The back-end supports any n×n board game, so the front-end can be extended to include more Tic-tac-toe type games. Decentralized Mobile Applications Supervisor: CHATZOPOULOS Dimitrios / CSE Student: TSANG Lok Kan Ethan / QFIN Course: UROP1100, Fall This paper is writen based on my previous publication of ”BCred - A Blockchain Platform for Academic Credentials”. BCred is an blockchain application idea proposed on the International Blockchain Olympiad 2020, intended to develop a complete, efficient, yet secure system for academic credentials. In this paper, I will illustrate the basic set up and cautions for general decentralized mobile applications development. In Section 1, I will give a brief introduction on distributed ledger technology (DLT), blockchain, decentralized applications (DApp), in addition to BCred. In Section 2, I will frame the basic set up and prerequisite for decentralized application development. In Section 3, I will illustrate the simple implementation of decentralized application based on BCred. In Section 4, I will elucidate some cautions and guidline for decentralized application development based on two publicly trusted and recognised publications. Decentralized Mobile Applications Supervisor: CHATZOPOULOS Dimitrios / CSE Student: EDRIC Jovan / COMP Course: UROP2100, Spring Blockchain technology was first introduced as a method of securing financial transactions. It has since evolved into something much broader. The advent of smart contracts, in particular, has brought into fruition the feasibility of decentralized applications, to run and execute turing-complete code in the blockchain, all while taking advantage of the tamper-proof nature of the blockchain. Despite this, the centralized nature of conventional internet applications offers more flexibility, as a tradeoff, when compared to decentralized applications. The proposed decentralised application offers a marketplace for consumers and service providers to buy and sell services, by adopting a middle-ground approach, securing transactions in the Ethereum blockchain and storing overhead user meta-data in a centralized cloud database.