Whenever I travel, my iPhone becomes my communication workhorse: My go to device for talking to customers, to team members, to friends, to family. However, there's a definite shift taking place in how I use this device. I've just returned from two weeks in Munich and checked my usage. While away, I used only 17 minutes of traditional voice calls. However, on the data side of the house, the figures were a little higher. I racked up 200 megs of data roaming. O2, you're welcome. And my data usage was drastically higher over WiFi.

In fact, what amazed me most was how WiFi actually directed my travel. There were only a few occasions when I wasn't connected to a WiFi network. From my hotel to bars to restaurants, one of the first questions I asked was, 'Does it have WiFi?' If the answer was no, I'd more than likely look at somewhere else (a note for any restaurateurs). For any regular readers of the blog, this should come as no surprise. I've discussed on numerous occasions the importance of WiFi and the need for increased adoption of WiFi blankets.

I'm certainly not alone in favouring WiFi over 3G though. Take a look at the latest figures from Actix, a mobile network analytics company. It analysed data from a live 3G network in a major city and found that over 90% of iPad and iPhone 4 usage is indoors. These figures are incredible, especially for iPads. Only 5% of iPads are using cellular networks. Imagine if these numbers reflected global usage. There’s a wealth of untapped revenue waiting to be exploited here.

Part of the reason why iPad users favour WiFi is highlighted by industry analyst Chetan Sharma, who notes that 90% of all tablets sold in the U.S. in 2011 were WiFi only. Although a high figure, we shouldn’t be surprised by this number. There are clearly a number of reasons for this trend. Firstly, the additional cost of 3G/4G models. This is simply a premium that many don’t want to pay, especially if they already own a smartphone. Secondly, the lack of attractive subscription plans from mobile operators, especially plans that stretch across multiple devices. Ultimately, I want all my devices on one plan. I don’t want one plan for my iPhone, another for my iPad, etc. What’s more, I want a plan that covers my entire family and offers discounts accordingly. The industry has some way to go before achieving this.

Will these figures change with the new iPad and the continued rollout of 4G networks? Time will tell, but there can be no question that 4G data packages are currently cost prohibitive.

Aside from the importance of WiFi connectivity, I'm also amazed at the rapid change in the way I use my iPhone. I talked a lot when I was travelling but only used 17 minutes of voice calls. The reason - Skype, FaceTime, Google Chat and other over-the-top services. Spending so much time on WiFi enabled me to use my iPhone and iPad to talk to people over video and not just expensive voice calls. I even did a little of this on 3G networks.

Again, I'm not alone here. Taking another look at the figures from industry analyst Chetan Sharma, we can see that 85% of the traffic on U.S. mobile networks is now data. This figure is astounding. What's more, Sharma expects this figure to increase to 95% by 2015. Figures from Akami support Sharma's findings, noting that mobile data doubled from Q4 2010 to Q4 2011. This seismic shift has huge implications for the mobile industry. As I've discussed previously, the business model for mobile carriers needs to evolve to support this migration from voice to data. Simply raising costs will provide some short-term relief but is no long-term solution.

Sharma believes that there are two clear opportunities ahead. The first focuses on taking advantage of the data being generated to enhance the user experience. The second involves developing new technologies to manage the exponential growth in data traffic.

It will be fascinating to see how the mobile landscape develops over the next few years and how our own usage of mobile devices evolves. I'd be interested to know how you're using your mobile devices. Do you find yourself seeking out WiFi hotspots more than previously? Are you using more over-the-top services as opposed to your bundled voice minutes? Let me know.