With the introduction of 3G, and especially 4G, mobile Internet access is no longer considered inferior to home broadband. In fact, in certain locations it can actually be much faster than many residential DSL plans. That said, as you roam around, even within the same city, you'll experience changes in speed and coverage because it is still just a cell data connection.

The good: Compact and good-looking, the T-Mobile Sonic offers mobile Internet access for up to five Wi-Fi clients via T-Mobile's 4G and 3G networks. The device has long battery life, works as a tethered modem, features an SD card slot and supports text messaging.

The bad: Data speeds could use some improvement, comparatively. Its included limited-data plans are rather expensive, and the router's connection speed is throttled when the monthly data caps are reached.

The cost: $99.99.

The bottom line: Well-designed and reliable, the Sonic makes a very good travel companion. 3.5 out of 4 stars

The good: This mobile router provides fast cellular Internet access to up to eight clients at a time, with affordable unlimited data plans. The Apollo incorporates a large LCD that shows helpful information about the device, and the battery lasts a long time.

The bad: The Apollo doesn't support 3G, Wireless-N or text messaging and is comparatively bulky.

The bottom line: For those who live or travel within Clear's 4G coverage, the Clear Spot 4G Apollo is an excellent mobile-broadband option. 4 out of 4 stars

The good: Good-looking, compact, easy to use and features Wireless-N. The device comes with an affordable unlimited 4G data plan, includes GPS and network storage functionality, and has decent battery life.

The bad: Sporadically doesn't work well with certain Wi-Fi mobile devices and can support only five wireless clients at the most. The device runs hot at times and its 4G connection is comparatively slow.

The cost: $0.00 to $79.99.

The bottom line: For mobile users who travel within good Sprint 4G coverage areas -- especially those with laptops -- the Sprint MiFi makes a good companion. 3.5 out of 4 stars

The bad: Comes with expensive and limited data plans that throttle down Internet speed when the data allowance is reached. The modem itself is rather bulky and its download speed fluctuates a great deal.

The cost: $79.99.