Yes, you can access all your sites via your Company account in the Installer app if you have app version 2.3.3 or above.
To create a Company account, or to join one, see Joining or Creating an Installer Company.
Updated
Yes, you can access all your sites via your Company account in the Installer app if you have app version 2.3.3 or above.
To create a Company account, or to join one, see Joining or Creating an Installer Company.
Updated