Anki’s source code can be found on GitHub, along with instructions for building the platform in the docs/ folder. If you run into any issues during the build process, the expectation is that you should try to solve them on your own. If you’re not familiar with programming, it is recommended to use the packaged version instead. If you encounter bugs while running Anki from source, it’s worth checking if you can reproduce them in the packaged version, as certain system libraries like Qt can possibly cause problems. AnkiMobile is a paid companion app for Apple devices, while AnkiDroid is a free Android version based on the desktop code.
https://apps.ankiweb.net/