Whenever Quentin Barnes watches old movies/videos, they're always called holos... short for holograms.  However I'm not certain the term is used for live communications as well.

I know in The Starter there's a point, near the beginning of the story, that John, Ju & Ma Tweedy are speaking via what I remember as some type of video call... like FaceTime on an iPhone. I can't remember if it had a specific name (and it annoys me that I'm at work and can't look it up right now). 

[flickr-photo:id=5353037802,size=m] & Proud member of the Gutter Sistren

The call gmork is talking about I don't think had a "name" as such. They did say that everyone was on a "central holotank" so it seems like it was integrated into the holo-interfaces. But that's 300 years after the Crypt, so it is probably more sophisticated.

On the military side, in Passenger they use something I think they called a J-Plant, which was a communication interface integrated into the jawbone and the ear directly. Tapping on the jawbone in different manners changed frequencies and that kind of thing. This was used extensively in Passenger. so you might check there for behavior. The Crypt takes place some time after Passenger, though i forget how long.

Again, that's military. If you're talking civilian, I can't think of anything off the top of my head. I suppose it's not unreasonable to assume that a J-Plant sort of device may be available, but maybe only on limited frequencies. Also on the military side, you might want to check out the Shonda Bible story at http://www.scottsigler.com/node/3834 to see what they use to keep in touch between the different mechs.

_________________________________________________________

Gutter Sistren whipping boy, innoventor of words, Life Coach to the Damned.

you are the man for the job! YOUR RAWK!
[flickr-photo:id=5353037802,size=m] & Proud member of the Gutter Sistren

Would there be a system like that in use in the future?

Soon to be starring in NOCTURNAL by Scott Sigler. The autograph line starts to the right.

Quentin lifted the thing to dangle over his lips. He opened his mouth and started to lower it, when Virak's phone buzzed loudly. Quentin set the critter down, pretending to be polite, as Virak answered the call. The Quyth Warrior's eye changed from orange, the color of happiness, to pitch black almost instantly.

"What's the matter," Quentin asked as Virak put the phone away.

"Donald Pine is in the hospital. He has been attacked." (Sigler, 2009, p323)

You like that tasty citation? I had to dust off my APA Publication Manual for that :)

I am crazier than a padded room full of Charlie Mansons!

Sgt. Renee Jordan PUMC, PUV James Keeling

...the J-Plant was League of Planets tech, not Planetary Union.

There's also the palm-up holo displays that are used throughout the Crypt-timeline and the Rookie-timeline (like in the latest chapter of The Starter).

Who said anything about ownership of technology?

_________________________________________________________

Gutter Sistren whipping boy, innoventor of words, Life Coach to the Damned.

If civilian, it's going to be an occular implant. Imagine your smart phone, but the screen is your own cornea. You turn it "on" by looking up and blinking a pattern, turn it off the same way. This allows instant video chat with anyone in range. So short answer: cell phones are in your eye.

Now some civvies are smart enough to know that a direct link to your brain, in any form, is a bad thing. I would have one. A cautious tech-wizzard like Cory Doctorow would not.

If military, and in the Planetary Union, they frown on personal implants. The Union is behind the tech curve when compared to the League of Planets and the Prawatt Jihadd. The Union likes soldiers to be implant-free, but there are many exceptions. First and foremost, the "wireheads," guys who have multiple cerbral implants so they can work ship systems at the speed of thought.

So, if it's a Planetary Union solder who is not a wirehead, probably has a pocket phone not that much different from what we have today. It would be a "palm-up holo." Removable ear implants (like a BlueTooth headset) are common, but the Union military's obsession with using easily removeable tech makes soldiers tend to avoid even those.

...and everybody else. My character is a civilian, and while he may have concerns about implants, his need to be connected outweighs them. So an occular implant sounds like the device I need.

That answer leads me to another question, however. This comes dangerously close to a spoiler, so in the event that my story is featured on Tuesday Terror, listeners may not want to read this part. I'm doing what I can to keep people from reading it accidentally. Here goes:

Did that work? Hope so. Anyway,

Since the Planetary Union frowns upon implants, what would happen if a civilian with occular implants is forcibly conscripted into the Planetary Union military? Now that we've established that occular implants are exactly what my character would use, it would be a cop-out to not use them in an effort to avoid the narrative complications the ywould lead to. Which might actually be a good thing, because those complications might be horrifying.