The holy grail of mobile technology is to be always connected with good bandwidth and devices that let us do what we want.

Most of us are only part-way there - about half of us have smartphones. These let us always be connected to email, the Web, and more - until we travel out of country and face high roaming fees. And while convenient, actually working on smartphones is less than ideal - at least for me.

I can be more productive on a laptop but find those often more bulky than I want to carry around. And laptops use WiFi to connect - good if there's a nearby hotspot, but far from always connected. (Yes, I could share a smartphone's mobile data with my laptop or use another gadget to connect.)

For the past couple of years, my portable technology of choice has been one of Apple's original iPad models. I'm one of the 20% or so of iPad owners who paid a $130 price premium to get a mobile data-enabled model letting me use a WiFi hotspot when available or other times connect to a mobile-carrier's data network - at least when I'm in Canada.

...some hotels promise free WiFi but actually provide only an hour of free access.

Last summer, I reported that I'd found it easy and affordable to replace the Canadian SIMs in my iPad and a loaner HTC Android smartphone with ones purchased from Vodafone Italia. These let me access the local network - so no roaming charges - and automatically stopped working after a month. (The trick was to have hardware that was not locked to a specific service - iPads are all unlocked, but most of our phones are not.)

This spring, I was in New York City for a week, again with my iPad, and again wanted short-term access to a local mobile data network. An AT&T store near my hotel was happy to provide me with a SIM for a month's service for about $25. More time than I needed, but no problem - I thought.

I've learned to make sure I can connect before I leave the shop. Like Canada's Rogers, AT&T provides SIMs that are pre-activated; when plugged in, software appears on the device allowing the user to pick a plan, enter credit card information, and get online.

Slick and handy. But AT&T's software required me to enter a credit card with a US address. No zip code, no service. Sorry. Apparently, there was no way they could take my money.

Competitor T-Mobile was two doors down the street. It could sell me a SIM good for a week's service for $10 - a better fit for my travel plans. Unlike AT&T, its card had to be activated by a salesperson - who needed to phone tech support to learn how to do it.

But after 10 minutes, I was up and running - as tested before I left the store.

My SIM card adventures weren't over, however. The micro-SIMs used by iPads are about the size of my baby fingernail. So I cleverly taped my Rogers SIM onto the back of a business card I'd picked up at the AT&T store to make sure I wouldn't lose it.

Smart idea - except I threw the business card away while cleaning out my wallet. Back in Canada, a $10 replacement SIM and 20 minutes on the phone to Rogers' support got everything back to normal.

One more travel tip: Hotel WiFi often isn't all you might hope - some hotels promise free WiFi but actually provide only an hour's access for free. And even where the promised free connection really exists, bandwidth can be poor with a router down the hall somewhere serving multiple rooms.

A portable WiFi router such as Apple's Airport Express (the newest version, which also supports streaming video, is $89 shipped from Amazon.com) is worth packing. About the size of a cigarette pack, it plugs into an electrical outlet and connects to a wired ethernet network port - often (though not always) found in hotel rooms, giving you your own WiFi connection. Just don't forget to pack an ethernet cable!

First published in Business in Vancouver June 12, 2012 High Tech Office column.