Perhaps against the odds, RCS, or rich communications services, is still alive and kicking at many operators across the globe. If meaningful consumer traction and service revenues are to be attained, however, the standard's promoters and supporters need to overcome the major challenge of interoperability.

Announcements this week ahead of the Mobile World Congress trade show (see below for the details) suggest the RCS community has realized it needs to initiate much greater levels of collaboration if RCS is to deliver applications that can in any way rival those of the over-the-top (OTT) players.

It's no surprise that the Barcelona-based mobile extravaganza is the launch pad for RCS initiatives, as the event organizer, the GSM Association (GSMA) , is also the force behind the RCS specifications, which encompass advanced communications services -- including video calling, presence, photo sharing, and enhanced messaging -- built on an IP Multimedia Subsystem (IMS) backbone. (See Spain Gives RCS Camp Some Hope.)

These are the kind of apps with which OTTs have found wild success in recent years, while operators have floundered. RCS is viewed by its supporters as the competitive response to the OTTs, but it's been exceedingly slow to take off, especially in the US, where operators have instead focused on voice-over-LTE (VoLTE) and other ways to claw their way into the value chain.

That is starting to change, though. According to the GSMA, 41 operators in 32 countries have now launched RCS-based services and 87 more have committed to launching them by the end of 2015.

What is more important than individual launches, however, is ensuring the services are interoperable across carriers in the same way as regular voice and SMS services. That's where a number of vendors are stepping in to help provide that interconnectivity and move the market along.

For more on RCS, head over to the dedicated VoLTE/rich communications content channel on Light Reading.

Genband Inc. , for example, has announced the fring Alliance, extending its 2013 acquisition of white-label, OTT chat app fring to all service providers looking to develop native messaging, voice and video services that interoperate with others. The company is creating a shared directory of all its subscribers to let participating operators reach all of them and claims it's fully interoperable with RCS. (See Genband Acquires fring to Help CSPs Go OTT.)

And, in related news, Tropo has teamed with Apcera and IBM Corp. (NYSE: IBM)'s SoftLayer to launch Tropo Connect, a cloud-based platform to enable the embedding of intelligence into live phone calls and text conversations. While it isn't contingent on RCS, Tropo's CTO Jose de Castro says it can enhance any voice or video conversation with analytics, recording or by bringing in new web-connected devices to the conversation.

"RCS is about allowing new types of connections (voice, video) while Tropo Connect sits in the middle of those conversations and enhances them with apps and cloud services," he writes in an email to Light Reading.

DT, Sprint, Vodafone and KPN join the Jibe Hub
The most interesting development, by virtue of its telco involvement, comes from Jibe Mobile , which is announcing new operator participation in its Jibe Hub, designed to interconnect RCS services. Deutsche Telekom AG (NYSE: DT), Sprint Corp. (NYSE: S), Vodafone Group plc (NYSE: VOD) and KPN Mobile have all joined the Hub and, at MWC, will be demonstrating video calling, group messaging and photo sharing across their networks on Sony Corp. (NYSE: SNE) Android devices. (See Sprint Jibes With OTT Comms.)

When Jibe first launched the Hub this time last year, Deutsche Telekom was the only one to sign up, so it is moving in the right direction. Kobus Smit, head of voice and messaging at DT, says the carrier will begin connecting to the Hub later this year across Europe and will move its current direct interconnect agreements -- for example, with Telefónica in Germany -- to the Hub. (See DT Backs Jibe's Cross-Carrier RCS and DT, Jibe Bring RCS to Romania.)

"The Hub crosses national and international borders, which is what makes it very important," adds Jibe CEO Amir Sarhangi says. "It makes the process of interconnecting more efficient and time to market is faster."

Sarhangi says the most significant RCS-related advance of the past year is the evolution from being available only as a separate downloadable app to being integrated with a device's native dialer. Now consumers don't see it as yet another chat app, but rather an evolution of SMS. They default to RCS for a text when messaging a compatible smartphone, and fall back to SMS when the recipient's device or operator doesn't support it, much the same as Apple Inc. (Nasdaq: AAPL)'s iMessage. They can also do video chat and share multimedia without firing up another app. (See Samsung Dials Up RCS for VoLTE.)

"If there's no reason to churn off it -- cost or lack of feature set -- you stick with it," Sarhangi says.

Most Android devices now support the technology natively. Only Apple remains RCS-less, but iPhone users can download an RCS app. Its participation would be a big boon to the specification but, in the meantime, Jibe is hoping to get more operators on board with the Hub, including in the US where service providers are beginning to explore RCS more as an add-on to VoLTE. (See Sprint Plots RCS-Laden Path to VoLTE , MTS Preps RCS With Mavenir, Libon Liberates Orange From RCS and Telus Preps for VoLTE, RCS.)

"The more carriers you can bring on, the more valuable the Hub becomes," Sarhangi adds. "You connect once and can reach everyone. It would be pointless for people to think about the Hub if there wasn't greater momentum around RCS, but the question [about whether] RCS is the right standard has gone away. Now it's about how to interconnect."

— Sarah Thomas, , Editorial Operations Director, Light Reading