Jun 7, 2011 20:41 GMT  ·  By

On Monday, during the keynote address at Worldwide Developers Conference in San Francisco, Apple unveiled a wide range of new features as services coming to its users in iOS 5, including iMessage, a service that could prove a direct competitor for the messaging systems that wireless carriers offer to their customers.

The new iOS-to-iOS messaging service was designed to offer users the possibility to easily send text, video and picture messages from an iOS-based device to another over Apple's internal network, over Wi-Fi or 3G.

In short, the new service would eliminate the need to subscribe to a specific messaging plan with the wireless carrier, at least for those who have many friends using the iOS devices.

The new service is available for free, although it has some limitations. Here's what Apple notes on it:

iMessage in iOS 5 brings the functionality of iPhone messaging to all of your iOS devices―iPhone, iPad and iPod touch.

Built right into the Messages app, iMessage allows you to easily send text messages, photos, videos or contact information to a person or a group on other iOS 5 devices over Wi-Fi or 3G.

iMessages are automatically pushed to all your iOS 5 devices, making it easy to maintain one conversation across your iPhone, iPad and iPod touch. iMessage also features delivery and read receipts, typing indication and secure end-to-end encryption.

Rumor has it that some carriers might move against the new service, and that they would even consider blocking it for their customers.

However, since there are a wide range of other similar applications and services, chances are that wireless operators won't feel directly threatened by the new iMessage.

One rival that could be affected by the move would be Research In Motion and its BlackBerry Messenger (BBM) platform, which was recently announced as being on its way to various mobile operating systems out there, in addition to RIM's own OS.

Jefferies analyst Peter Misek believes that BBM is better positioned at the moment, courtesy of RIM’s NOC/node infrastructure, through which messages can be sent without a data plan.

“The launch of a low-cost iPhone in the Fall targeted at prepaid and emerging markets will only further undermine RIM,” he stated, International Business Times reports.