A major limitation of WinRT apps in the enterprise has been the licensing model. In the past companies were asked setup an Active Directory or pay 3,000 per hundred computers for side-loading keys. As part of the Windows 8.1 Update that requirement has been considerably softened.
Under the new rules, companies with Open License agreements can purchase a Multiple Activation Key for approximately 100 dollars. This key, also known as a MAK, is needed for any Windows 8.1 RT, Pro, or Enterprise computers not part of a domain. Windows 8.1 Pro or Enterprise computers that are part of a domain can sideload apps by following the directions on TechNet. Standard versions of Windows 8.x only support sideloading if it is outfitted as a developer’s rig.
Other problems with using WinRT apps in the enterprise continue to persist. Aside from the obvious lack of support for older machines running Windows 7, there still isn’t a good way to distribute WinRT apps within the enterprise. Rockford Lhotka writes about three options,
Microsoft offers InTune, which is a full MDM (mobile device management) product. If you find the value proposition of an MDM compelling then InTune is probably the right answer for you – though there’s a per device/per month cost (ranging from $6/device/month to $11/device/month) so you don’t get MDM for free of course.
I’ve been coordinating an open source project called OrgPortal that you can use to (relatively) easily create an app store for your organization.
There’s another open source project called CompanyStore that is very similar.