Applications for the iPhone 3G are popping up all over the map as software developers rush to support the new Apple wireless phone that is expected win more converts among business users.

One of the latest entrants is Mailtrust, a business e-mail storage specialist and a division of Rackspace Hosting. Mailtrust announced on July 15 that it now supports wireless data synchronization for iPhone 2.0 software, which runs on the 3G.

Mailtrust's Hosted Exchange 2007 already works with ActiveSync for Windows Mobile devices and will now offer that same functionality, including push e-mail, calendaring and contacts, for iPhone users.

"Mobile device support, once a luxury for messaging users, is now an absolute necessity," said Daniel Golding, vice president and research director of Tier1 Research, a division of The 451 Group. "Support for the top devices—RIM's BlackBerry and Microsoft's Windows Mobile—have been vital for managed messaging providers to achieve a foothold in the highly competitive and demanding enterprise messaging segment.

"The Apple iPhone, while originally envisioned as a personal device, has morphed into a powerful enterprise smart phone with its latest software and hardware releases. Tier1 expects significant enterprise iPhone adoption, making managed messaging provider support for the Apple smart phone a sharp move."

Exchange Active Sync maintains a secure connection between the Exchange Server and the iPhone so that when a new e-mail message or meeting invitation arrives, the iPhone is immediately updated.

Mailtrust has about 800,000 users with some form of mobile access to either Hosted Exchange or Noteworthy, a business-class alternative to Microsoft Exchange.

Current Mailtrust customers with a Hosted Exchange 2007 account can download and install the new firmware since Apple made the software available to consumers at large on July 11.

Mailtrust said it is currently developing options for syncing the iPhone with its Noteworthy platform.