You can use your telephone to call any other phone in the world. But if you want to place a video call to someone, good luck.
Thanks to the incompatibility between video calling services including Skype, Google Hangouts and Apple's FaceTime, there's a good chance that the person you want to reach isn't on the service you use.
If you want to reach someone, you have to know what video calling service that person uses, make sure you have access to that service and, in some cases, know the nickname the person uses on that service. And to ensure you can connect with a wide range of people, you'd have to run multiple applications.
Imagine if AT&T cellphone users could only call other AT&T customers and Verizon Wireless customers could only call other Verizon Wireless users. To reach everyone, you'd have to have a cellphone for every network.
And yet, we consumers have had to deal with this situation for years when it comes to Internet-based communications technologies. PC-based instant messaging has long suffered the same problem as video calls. You still can't use AOL's AIM chat application to send a message to someone using Yahoo's Messenger service, even though both have been around for more than 15 years.
And we're likely to have to continue to suffer with incompatible messaging services for years to come. That's because newer mobile-based messaging apps - including WhatsApp Messenger, Apple's iMessage and BlackBerry's Messenger - are generally closed to outside connections.
Cullen Jennings, a Cisco fellow who is working with the Internet Engineering Task Force to develop standards for messaging technology, is optimistic that the various messaging services will eventually connect with one another-just not anytime soon.
"That's looking more in the 10-year time range," Jennings said. "This is a slow shift."
The problem, he said, is not a technical one. Many messaging and video calling services are built using the same Internet standards, so allowing the services to interconnect would be relatively trivial.
Instead, he and other analysts say, the lack of interoperability has more to do with companies focusing on their own narrow business interests. Messaging service companies are still trying to figure out how to make money and think that to be competitive, they've got to accumulate as many users as possible, analysts say. So they are more interested in locking in new customers than in allowing their existing customers to connect with friends on rival services.
Meanwhile, there's little to no government pressure pushing companies to cooperate. Governments could mandate that telephone networks interoperate, because those networks were controlled by a limited number of heavily regulated companies. But many of the newer messaging services are offered by startups that fall outside of existing regulations. Even the services offered by giant companies like Apple or Google haven't yet seized enough control of the market to draw regulatory scrutiny.
To be sure, there have been some stabs at interoperability over the years. Apps such as Trillian and IM Plus allow users to sign into multiple messaging services at the same time. You can use AOL's AIM or Yahoo's Messenger to send instant messages to friends on Facebook, and can use Skype to make video calls to your Facebook friends. Apple's iMessage allows iPhone users to send and receive regular SMS text messages. And the Skype app has long been able to make voice calls to regular telephones.
But the connections are disjointed at best. And for every step toward integration, there seem to be other steps away from it. Microsoft replaced Windows Messenger, which connected to Yahoo Messenger, with Skype, which doesn't. Google's now-retired Google Talk chat service was built on an open standard; its Hangouts service is built on proprietary technology and unlike Talk, doesn't allow users to communicate with AIM or other outside chat services.
And then there's Apple. When the company launched its FaceTime video service, then-CEO Steve Jobs announced the company would make the technology behind it an "open industry standard," which would presumably allow non-FaceTime users to make video calls to those using Apple's app. More than three years later, the iPhone maker still hasn't followed through, and FaceTime remains as closed today as it was then.
The IETF's Jennings remains optimistic. As adoption rates slow, he said, messaging providers will come to realize that they can provide more value to their users by tapping into the network effects of connecting to other networks than by keeping users locked into their services. And corporate clients and regular consumers will push the messaging providers in that direction.
Maybe so, but even Jennings admits that day is a long way off. So for the time being, we're stuck with an unruly mess of messaging systems, none of which wants to talk to the other.
Explore further: Top banks launch integrated messenger service