Sprint Nextel today introduced a push-to-show feature for its Nextel product line, allowing customers to use the same Direct Connect push-to-talk channel to instantly send photo files.

The new application resembles MMS, but with crucial differences such as its immediacy and integration into the Direct Connect service, said Beverly Hodges Little, who oversees the push-to-talk product groups for Sprint. Instead of establishing a separate data connection and sending a delayed MMS over the network, the Direct Send feature uses the push-to-talk channel to establish a direct IP connection to another customer’s phone—the picture automatically begins rendering after the one-second delay it takes to establish a connection.

What’s more, Hodges Little said, the multimedia doesn’t monopolize the resources of the Direct Connect Channel, meaning customers can hold push-to-talk conversations while sharing photos.

This kind of service is the precursor of more advanced “push” services the industry is developing. Companies such as Motorola, Kodiak and Sonim have been developing push-to-talk applications for CDMA and GSM networks that eventually will allow almost anything to be pushed to the user, from video and other multimedia files to data files.

So far adoption of push-to-talk beyond the iDEN networks used by Nextel has been hampered by the limitations of other network technologies, including that used by Sprint’s CDMA network. Receiver activation times have created delays in establish direct connections as high as five seconds in many networks, limiting the usefulness of a push-to-talk service. But Nextel’s network, optimized for push-to-talk, has allowed it to move forward with more advanced services, while other carriers try to get their basic voice applications off the ground, Hodges Little said.

“We’re leapfrogging the market, looking to what’s next,” Hodges Little said. “By the time our competitors figure out the basic technology, we’ll be far ahead with other push-to-X applications.”

Direct Send is now available over the new Motorola i870 handset, which was released pre-loaded with the software, and will be available over all future Nextel phones with camera capabilities. Sprint said it would also make the service available to current camera phone users in coming weeks, allowing customers to download a software upgrade for five other iDEN handset models. Nextel is offering the service for free until Feb. 28, but after the promotional period will begin charging 25 cents per picture sent.