BlackBerry maker Research in Motion Ltd. tacitly acknowledged the inroads Apple Inc.'s iPhone and devices based on Google Inc.'s Android software are making in the corporate smartphone market, with its recent decision to offer companies tools for managing and ensuring the security of BlackBerry rivals.

Due to its messaging capabilities and security, the BlackBerry has long dominated the corporate market. Data sent over RIM's BlackBerry network is heavily encrypted, and corporate information-technology departments have a...