In yet another blow to RIM’s formerly solid hold on security-minded enterprise and government clients, the U.S. Department of Defense (DOD) will soon allow some employees to use iOS and Android devices in the course of their duties.

The Washington Post reports that a DOD document shows it plans to hire a contractor to manage “at least 162,500” Android and Apple devices. It is also possible that deal may expand to as many as 8 million devices.

BlackBerry devices are already used at the DOD, as is the case with many clients who need enhanced security features for mobile devices. However, RIM, the makers of BlackBerry, has seen its share of the U.S. smartphone market dwindle this year and some corporate clients have begun abandoning BlackBerry-only mobile device policies.

Just two weeks ago, government consulting company Booz Allen dropped BlackBerry as its phone provider, stating that its 25,000 employees will be moved to Android or iPhone devices in the coming months. In September, Yahoo CEO Marissa Mayer informed all Yahoo employees that they will be receiving their choice of the top iOS, Android, or Windows Phone 8 smartphones. BlackBerry devices, which many Yahoo employees previously used, were conspicuously left out of the memo. Mayer emphasized that Yahoo employees should be using the same devices that Yahoo users do.

The DOD isn’t dumping RIM completely, however. The Post article states that the department “desires” a system that can also handle BlackBerry devices, though is not insisting on it. RIM’s VP of government solutions told the Post that the reason for this is that the DOD already has a system for managing RIM devices.

(via BGR)