John,
Traveller has already touched upon everything you mentioned.
According to the 1983 module Tarsus, people on that backwater world use personal satellite phones for a variety of purposes including communications, data processing, and even voting.
Seeing as this particular issue was addressed over twenty five years ago, would you like to suggest some other technological aspect that allegedly needs "updating" or "rethinking"?
Were these devices described as ubiquitous or as speciality items for military and emergency service personnel and perhaps the wealthy?
Also, my point wasn't just about TL 10 worlds like Tarsus, but also the TL 5-8 worlds, where I can't imagine that free traders wouldn't have sold every non-Red Zone world that wasn't inhabited by either technophobes or people who were edge-of-starvation-level poor, a full range of comm, GPS, and weather satellites and regular shipments of trunkfuls of TL 11 smartphones (which would likely be on the order of the best smartphones available today, but with processor speeds and memories of modern desktops, and perhaps a few more bells and whistles, like night vision on the camera and real-time language translation to known languages for both text and speech). I'd expect every well off (upper middle class on up) citizen of such worlds (something like the top 10-20% of the population) to have such a device if they wanted it. Also, I'd imagine that at TL 11 or so, manufacturing a durable low end cellphone, like a modern non-smartphone, would be exceptionally cheap and fast, and so traders could sell even more of these things to the entire middle class of such worlds at a good markup.
So, much of this tech would be ubiquitous throughout the Imperium, including low tech worlds. The low tech poor won't have them, and the low tech working class may not, but everyone else will.
Then, you add in the fact that we have the first generation of augmented reality devices in use right now (see:
http://www.google.com/mobile/goggles/). I'd expect a whole lot more of at TL 10+. So, at TL 11+, you point the camera on your display glasses or hand computer at a sign in Aslan or some known Imperial language, and it's automatically translated to the language you set as the default. You point the camera at a plant or animal in that's in library data (and I'd expect pretty much anything you're likely to encounter on any world that been in the Imperium more than a century or two to be in library data) and you get a brief description of the plant or animal (presumably accompanied by any dire warnings that may exist), and a link to click for more detailed information. On many (perhaps most) TL 10+ worlds, most or all people will also have links, so that when you point the camera at them (and if the camera is on a pair of display glasses, this essentially means you look at them) you'll get the local equivalent of the public portion of their Facebook profile. That, and all this is at least as easy to use and at least as familiar to characters from TL10+ worlds as ipods & cellphones are to middle class Americans under 30.
What I haven't seen in Traveller is much in the way of discussion of how TL 10+ technology (and especially TL 12+ technology) affects daily life. The world we live in is different thant that of the 70s, 80s, or even the 90s. I now reflexively look up information anywhere I have a wifi connection (using my ipod touch) and people who pay for data plans on their phones can do this essentially everywhere. This also changes how adventures are run. Look at modern-day adventure shows like
Burn Notice on USA (a truly excellent show) - you see the affects of ubiquitous data and communication on adventure plots. You don't see any of these sorts of effects in almost any video or written SF from the mid 90s or earlier.