Tiny Tic Tac Toe for Android

The classic tic-tac-toe game for Android and Linux/X11 written in C.

Features

It's tiny

Its APK file is smaller than 60 kB. For comparison:

The bar for Tiny Tic Tac Toe isn't visible because it's so tiny (about half a pixel).

Written in C

C is simpler than Java or Kotlin. Using C for this game results in super fast compile times, fast execution and small memory usage.

Developer friendly local execution

Run this game directly on your Linux/X11 machine during development. A clean build takes only 0.125 seconds (on my old laptop, using tcc: make x11 CC=tcc). X11 support is the biggest improvement over this project's inspiration VadimBoev/FlappyBird.

No Android app permissions required

Not requesting permissions is something rarely seen in Android apps.

Open source

Obviously, you have found the source code.

How to build

First, clone this repository:

git clone https://github.com/MaxGyver83/TinyTicTacToe.git
cd TinyTicTacToe

How to build for Linux/X11

Install these dependencies (Ubuntu 24.04 package names, might be different for other distributions):

• libasound2-dev
• libvorbis-dev
• libgles2-mesa-dev

The last one isn't necessary if you have installed the Android NDK (see next section).

Build and start TinyTicTacToe like this:

make x11

How to build for Android

Install Android Studio or Android's command line tools, the Android SDK and NDK.

This project expects these install locations and versions:

ANDROID_SDK_ROOT=~/Android/Sdk
ANDROID_NDK_ROOT=$ANDROID_SDK_ROOT/ndk/27.2.12479018
ANDROIDVERSION=35

If you use other folders or a different version of the NDK, modify the first lines of build_apk.sh, build_aab.sh, run.sh accordingly.

Optionally, copy/symlink your existing keystore to ./keystore.jks and export $KEYSTORE_PASSWORD and $KEYSTORE_ALIAS. Otherwise, replace "Your Name", "Your Organization" and "DE" in create_keystore.sh to get a keystore created.

Then start the Android Emulator or connect your Android device via adb connect and run:

make

Without any arguments, make will build and install an APK file containing code for all supported architectures, start the app on the Android device/emulator and start logging on your local machine.

Use make apk to build an APK file only.

Append ABI=<arch> to the command to build only for one specific architecture.

Examples: make ABI=arm64-v8a, make apk ABI=x86_64

How to build for Google Play Store

First, install Google's bundletool.

Then, create an Android app bundle like this:

make aab

To test the created .aab file on your Android device, run:

make run_aab

App in Google Play Store

This app is open source. You can compile it yourself and install it on your Android device for free.

If you want to thank me for sharing this code, you can buy this app in the Google Play Store:

https://play.google.com/store/apps/details?id=com.goodtemperapps.tinytictactoe

Variations

Texts prerendered as 32-bit PNG images

Originally, all texts used in this app were (32-bit RGBA) PNG image files created with create_sprites.sh using pango-view. This is much simpler than creating texts at runtime. Tiny Tic Tac Toe used upng for decoding the PNG files. Check out the png32bit tag for the original code.

Texts prerendered as 8-bit grayscale PNG images

There is a branch named png8bit that uses 8-bit grayscale PNG files instead. This reduces the APK size(s) by 8 kB.

Texts prerendered as 8-bit grayscale PGM images

But it turned out that 8-bit PGM files (Netpbm) are a better choice. This file format is so simple that it can be decoded without any library. Netpbm files contain uncompressed data. But after compression these files are even smaller than 8-bit PNG files. The best part is that it's not necessary to compress these files with gzip or similar because APK files are compressed anyway. This also means that Android decompresses these files automatically when accessed in C code.

Texts rendered during runtime using libschrift

Prerendering texts is simple but it doesn't scale well. If you want to create an app that uses much more text than this one, it might make sense to render all texts at runtime. Take a look at the libschrift branch which uses the libschrift library for text rendering.

Variations overview

Branch/Tag	APK size arm64-v8a	APK size x86_64	Assets	Libraries
png32bit	74 kB	74 kB	PNG files (RGBA)	upng
png8bit	66 kB	66 kB	PNG files (8-bit grayscale)	upng
main	58 kB	58 kB	PGM files	-
libschrift	53 kB	57 kB	a minimized font	libschrift

Contributing

I'm sharing this project to help you to start your own project. I want to keep it simple. This means I don't plan to add more features. I also don't care about squeezing every last bit of APK size or performance out of it.

But if you find a bug or want to add support for Windows/macOS/any BSD: Contributions are welcome!

Credits

Thanks to Vadim Boev for sharing VadimBoev/FlappyBird. Tiny Tic Tac Toe is very much inspired by it and re-uses some of its code.

The tick sound used in this game is from satrebor (Freesound) on Pixabay. I have reduced its length and file size using this command:

ffmpeg -ss 0.45 -t 0.15 -i pick-92276.mp3 -c:a libvorbis -q:a 4 pick.ogg

Thank you all!