One of the many prescient observations made by Steve Jobs during his lifetime came while being interviewed at the All Things D conference in 2010:

When we were an agrarian nation, all cars were trucks, because that’s what you needed on the farm. But as vehicles started to be used in the urban centers, cars got more popular. Innovations like automatic transmission and power steering and things that you didn’t care about in a truck as much started to become paramount in cars. … PCs are going to be like trucks. They’re still going to be around, they’re still going to have a lot of value, but they’re going to be used by one out of X people. … I think that we’re embarked on that. Is the next step the iPad? Who knows? Will it happen next year or five years from now or seven years from now? Who knows? But I think we’re headed in that direction.

Headed “in that direction” indeed, as worldwide smartphone shipments passed personal computers in 2011 and tablets are expected to do the same to portable PCs this year and all PCs in 2015. But as Android and iOS-based devices start relegating Windows-based PCs to specific tasks, is the same phenomenon about to happen to these mobile technologies thanks to wearable computing?

Wearable devices, which includes health trackers (i.e. Jawbone Up, Fitbit Flex, Nike+ FuelBand), smart watches (i.e. Pebble and many more expected from major consumer tech companies) and smart glasses (i.e. Google Glass), are projected to be a $50 billion business in 3 to 5 years according to Credit Suisse. But in order to reach that potential, wearable technologies need help from, coincidentally enough, the smartphone. That’s because wearable electronics lack the processing power and internet connectivity necessary to run their own native apps. So instead, these devices must leverage the latest Bluetooth technology in order to access existing mobile phone applications and wireless networks. This allows otherwise passive wearable interfaces to actively control the information being displayed on the device (i.e. YouTube videos on Google Glass or RunKeeper activity stats on a Pebble watch) or synched with the phone (i.e. steps tracked by Fitbit). Over time hardware technology improvements and more robust software will allow wearable computers to become their own app platforms, and in the process, relegate the smartphone to a subset of activities.

Which activities the smartphone focuses on going forward will depend on how consumers’ use of computing technology evolves. In keeping with Jobs’ analogy, if the personal computer is becoming the truck, then its primary purpose will be to enhance user productivity related to process-heavy tasks such as data extraction and manipulation, media editing and creation and software development. In turn tablets, because of their size and portability, are quickly becoming the device of choice when it comes to commerce, content, casual gaming and media consumption. This makes the tablet’s role more like that of an SUV rather than a truck. Even though smartphones will be used a lot like tablets when it comes to consumption activities, it will do so in shorter bursts of time and with specific intent (i.e. comparing product prices, looking up directions and movie times). Where the device will excel is in providing mobile connectivity akin to a MiFi device but programmed to route information in specific ways. Since smartphones will be used in the most variety of ways it should be considered the traditional car in the computing line up.

So where does that leave wearable computing? With a focus on specific activities per device type and efficiencies gained from not having to constantly interact with our smartphones, wearables might turn out to be the smart cars of the computing world.