If you want to block apps like vShare in your organisation you can now disable app usage from untrusted sources.
Log in to Xinca Management System and navigate to Profiles -> Create or Edit an existing profile -> Restrictions -> make sure Allow trusting new enterprise app authors is DISABLED.
(Allow trusting new enterprise app authors is disabled by default in new profiles)
Note: If the app has already been installed and trusted, then you need to remove the enterprise profile on the device. Also keep in mind that this will also affect trusting own enterprise apps, so if you want to distribute own enterprise apps you have to make sure this option is enabled during the installation!