On Thursday the Pentagon cleared BlackBerry and Samsung mobile devices for use on Defense Department networks, reports “Reuters” (http://tinyurl.com/csxzmrk). Apple mobile devices using iOS 6 are expected to receive clearance sometime this month.

“This is a significant step towards establishing a multi-vendor environment that supports a variety of state-of-the-art devices and operating systems,” Lieutenant Colonel Damien Pickart, a Pentagon spokesman, said in a statement.

The move to open up Defense Department networks is expected to set the stage for an intensified struggle for Pentagon customers among BlackBerry devices, Apple’s iPhones or iPads and units using Google’s Android platform such as Samsung Electronics’ phones, according to “Reuters.” The Pentagon currently has some 600,000 users of smart phones, computer tablets and other mobile devices. The department has 470,000 BlackBerry users, 41,000 Apple users and 8,700 people with Android devices. Most Apple and Android systems are in pilot or test programs.