If you use Intune/Endpoint Configuration Manager to manage your devices, you know that the Company Portal application is a key components.
The Company Portal application is used to deliver and let users install applications on their devices.
If your device is managed with Intune/Endpoint Configuration Manager, the Company Portal is now showing the Azure AD Applications (also known as Enterprise Applications) available on your tenant, including Azure AD Application proxy.
This is not available for co-managed devices.
These applications are categorized and there is no filtering to identify them.
The only way to identify such Enterprise Applications is when accessing the details of the application, it will show Azure AD Enterprise Application as Management Service and will only propose to open it with a web browser.
If you want to hide or add Azure AD application from the Company Portal you will need to contact your Azure Administrator to edit the Visible to users setting available in the Properties blade of the application.