Bixby is Samsung's own in-house virtual assistant, and is installed on all new flagships by default since the Galaxy S8 line's launch in 2017. Since then, Bixby (in its 1.0 iteration) lost compatibility with more and more Google apps. However, the latest update to Bixby 2.0 allows it to control YouTube, Google Maps and Gmail.
https://www.notebookcheck.net/Bixby-2-0-now-supports-more-Google-apps.396671.0.html