The three groups are apps that allow for "Signing in with Google," "Third-party apps with account access," and "Google apps."
It's obvious what Google apps are â things like Chrome and Drive. But here's how the two other groups differ:
Apps in the "Signing in with Google" section have access to your name, email address, and profile picture. But in some cases they may have access to more of your information â potentially a lot more, such as the ability to read and delete your email messages.
You likely gave the "Signing in with Google" apps permission to access such data because you wanted to use your Google login to sign into your accounts with them instead of having to create separate user accounts and passwords. But some companies that use Google's apps in their workplaces also require their employees to use their Google login to sign into other apps and services.
The "Third-party apps with account access" typically have access to much more than just your basic profile information. In fact, according to a Google support page, these apps often "can see and change nearly all information in your Google Account."
Developers whose apps have such access to your account can't change your password, delete your account, or use Google Pay on your behalf, but they can potentially read your email â or have their employees do it.
Some apps require those kinds of permissions to do what you've asked them to do. If you want to be able to use a mail app on your computer to manage your Gmail account or your Google calendar, it needs to be able to read and delete messages or appointments.
But you should make sure you trust the apps and developers that have such access to your accounts and that you are only giving them as much access as they need.