CASE STUDY
XO App (iOS)
Role:
Sole iOS Developer and Designer.
Tech Stack:
Swift, SwiftUI, Firebase Auth, Firestore, Git, GitHub
Project Overview:
XO App is a fast-paced twist on the classic Tic-Tac-Toe game. Instead of a single match, players compete against an AI opponent and try to win as many games as possible within 60 seconds. The app features role-based access: any user can play, but only signed-up users can save high scores and appear on the global leaderboard.
Goals:
Make Tic-Tac-Toe exciting again by turning it into a speed-based, skill-driven challenge against AI, with real-time score tracking and a competitive global leaderboard.
Development Process:
Built using Swift and SwiftUI, the app features smooth animations, sound effects, a countdown timer, and an AI opponent. Firebase handles authentication, score saving, and leaderboard ranking. I designed and implemented everything from gameplay logic to data syncing.
Challenges:
The real challenge was figuring out how to make my XO game stand out from the thousands of Tic-Tac-Toe games available in the App Store. I also had to design the logic to differentiate guest and registered users to control leaderboard access without blocking gameplay.
Solution:
After studying other Tic-Tac-Toe games on the App Store, I designed a unique game mechanic where users try to win as many games as possible within 60 seconds. To make it more competitive, I implemented user authentication and a global leaderboard using Firebase, allowing only signed-up users to compete for the top ranks, while guest players can still enjoy the game without saving scores. I really love how this game turned out.
Outcome:
Published on the App Store and praised by testers for its addictive gameplay loop. The competitive timer, smart AI, and global ranking system created a satisfying challenge for casual players and high scorers alike. The app supports both iPhones and iPads, and features dynamic styling that adapts to light and dark mode based on the user's system settings.
Contributions:
Designed and developed the entire app, including the game logic, AI, UI, animations, authentication, and leaderboard system, from the ground up.
Learnings:
This project strengthened my skills in AI programming, game loop management, SwiftUI animations, and Firebase integration, especially in designing short-session, leaderboard-based mobile games.
Completed:
October 2023
🚧 Temporarily unavailable — will be back once my Apple Developer Program is renewed.