Module Store
From MusicReader Manual
In the module store you can install, remove and update specific functions inside MusicReader.
Most of these functions are installed by default, but some might be optional.
If the module is installed then there is an update available then the page will show "Update" button.
Updates are also automatically installed when the App itself is updated.
Modules that are not installed show an "Install" button and installed ones a "Remove" button.