Remind me - Why do I need a smartphone?

Paying for a tablet PC and a smartphone seems like technology overkill

If research into the growth of smartphones is to be trusted, these devices are fast becoming a necessity in everyone's life, for personal and business purposes, and it's a trend that shows no signs of slowing.

Enterprises have noted this craze, with many opting to deploy smartphones across their organisations. Even UK police forces are using BlackBerrys because of the business efficiencies they can deliver.

However, there is now a new wave of gadget that commentators claim will again reshape the way we work: the tablet device. The most popular has been Apple's iPad, and it is beginning to take business by storm, having been deployed across a multitude of enterprises such as the BBC, the British Army, SAP, Lloyd's of London and even in UK schools. RIM is also preparing to launch its PlayBook device and Dell and Samsung, among others, are hoping to introduce their own devices, primarily targeted at business users.

So what does a smartphone do that these tablet devices are incapable of accomplishing?

Smartphones let you make phone calls and send text messages, but then so can any pay-as-you-go mobile phone, which you can pick up today for virtually nothing. Smartphones are also compact and convenient, but tablet devices are also designed to be easily transportable.

So how can a CIO justify splashing out on a mass deployment of both tablet PCs and smartphones?
As a consumer, I bought a bog-standard mobile phone on a pay-as-you-go deal a while ago. It was supposed to be a temporary, stop-gap measure, but I have not been sufficiently motivated to spend large amounts on a high-spec smartphone.

Smartphones do not come cheap and neither do tablet devices. An iPad, for example, will set you back a minimum of £429. Apple's latest smartphone, iPhone 4, costs from £25 per month on a 24-month contract, plus a handset fee of about £200.

So if I want both an iPad and an iPhone 4, I have to part with at least £1,200, which is a significant amount of money. If a CIO at an enterprise with 10,000 employees wanted to equip everyone with a smartphone and a tablet PC, they are looking at an outlay of a minimum of £12m for the first two years alone.

Is it worth spending those sorts of sums on equipping the workforce with two devices that do pretty much the same thing? And since a tablet has the capacity to offer so many more business solutions and applications than any mobile phone, it raises the question, why do I need a smartphone?