David_B adds an addendum!

Enterprise mobile device management (MDM) software is primarily a policy
and configuration management tool for mobile handheld devices, such as
smartphones and tablets based on smartphone OSs. It helps enterprises
manage the transition to a more complex mobile computing and
communications environment by supporting security, network services, and
software and hardware management across multiple OS platforms.

This is especially important as bring your own device (BYOD) initiatives
become the focus of many enterprises. It can support corporate-owned as
well as personal devices, and helps support a more complex and
heterogeneous environment. The primary delivery model is on-premises,
but it can also be offered as software as a service (SaaS) or through
the cloud. Although some MDM vendors also support PCs, this Magic
Quadrant focuses only on mobile capabilities.

Much more, here ...

http://www.gartner.com/technology/re...t=120518&st=sb