Instead of having to use the dedicated app, Google Meet is now integrated into Gmail for Android and iOS. For those who have the feature already, it's now a large tab at the bottom of the main Gmail interface. The company is still rolling it out, so you might not have the quick access to Google Meet yet. Google has made this videoconferencing app free for all users at the end of April. And it's continuing to add new features like this to attract more users. It's also visible inside new Google Calendar entries.
If you'd rather not have Meet on your Gmail app, you will need to turn off Meet integration in the settings menu.
Source: The Verge