Many providers, including AT&T, also allow the ability to "tether" a laptop or other device to a smartphone for an additional fee. But there are a few differences: for one thing, tethering can only be used with one device at a time; for another, it usually requires a USB cable or a Bluetooth connection which means it won't work with some devices, such as the iPad. AT&T charges $20 per month extra for this feature, though unlike Verizon's hotspot feature, the data you transfer while tethering counts against your smartphone's own data plan.

There are plenty of advantages to having your very own personal Internet hotspot. The first, is obviously, that you can connect devices to the Internet wherever you have a cellular signal. In some cases, this is a matter of financial savings as much as it is one of convenience: iPad users who also own a hotspot-capable iPhone, for example, would be able to save cash--both at the point of purchase by going with the Wi-Fi-only version of the iPad, and then again by avoiding the monthly fees associated with a separate cellular data plan.

In addition, there is the convenience of being able to rely on a single device for an increasing number of functions. Today, mobile hotspots are provided by dedicated products, like the , that have to be lugged around, bringing with them their attendant power cables, battery packs, and so on. Rolling that functionality into a single product will lighten pockets, reduce the amount of paraphernalia that needs to be carried around, and increase convenience.

There are drawbacks, though. From a technical perspective, the proliferation of personal mobile hotspots can lead to an increase in airwave congestion. Wi-Fi operates on radio frequencies that are publicly accessible--something that is not currently a problem as access points are usually far enough apart not to interfere with one another. In a future where everyone has a wireless access point in their pockets, public places that attract large crowds will become literally infested with radio signals vying for the relatively narrow band in which they are legally allowed to operate.