smartphones unlocked

By definition, the no-contract carrier model is designed to save you money over the two-year contract agreement that reigns supreme here in the U.S.

The question is: How much do you really gain by going prepaid, and what do you lose from the subscriber experience? Without a doubt, no-contract carriers like MetroPCS, Virgin Mobile, Boost Mobile, and Cricket Wireless can dramatically cut your monthly cell phone bill, but there are trade-offs.

I'm not going to dive into every carrier's pricing structure and phone offerings, so for the sake of comparison, I'm going to break down the … Read more

When you strip it all away -- the e-mail and texting, the voice navigation, and Angry Birds -- your smartphone isn't a smartphone at all. It's a radio.

The job of a radio is to detect, receive, and maintain the signal that leashes the cell phone to the network. When you turn on your phone, it chirps out data that lets the network know another cell phone has hopped on board.

The network authenticates the phone, and the phone is free to send and receive data or calls. In other words, more fundamentally than software and the processor, … Read more

Imagine a smartphone that charges completely in 5 minutes and lasts a full 10 hours before running on empty. Crazy, right? Toting along the charging cord is just another part of life with 4G streaming and a power-hungry screen.

Back in January, Motorola's Droid Razr Maxx offered the first real glimmer of hope for long-life batteries with the 3,300mAh ticker that dwarfed the battery in any other available handset -- it ran for 19 hours in CNET's tests, a longevity that hasn't been reproduced since.

That leaves the question I get asked over and over again: … Read more

Smartphones have become part of daily life but are often too delicate to withstand everyday abuse. Not so for the Sony Xperia Go, an Android handset built to shrug off treatment that would destroy typical mobile devices.

CNET UK took the Xperia Go for a spin, a few dunks, plus crevice-clogging dust-ups to put this rugged machine through its paces. … Read more

At 10:30 in the morning a few weeks ago I hopped into a plain white van, a mysterious briefcase carefully laid out on the passenger's seat abuzz with phones.

Into the afternoon, the driver answered my probing questions about long hours on the road, awkward run-ins with the cops, and flashed guns. This was no police surveillance ride along; my driver was merely sharing a day in the life of an independent cell phone network tester.

Meet RootMetrics A few miles away from Microsoft, a small company called RootMetrics (formerly Root Wireless) sends out a tiny squadron of … Read more

When Raymond Soneira compares smartphone displays, he doesn't just stare at side-by-side screens, using his highly trained eye to detect differences in color temperature and contrast. He does that, make no mistake, but he also uses a suite of scientific tests that measure factors like brightness, color gamut, and reflection.

Soneira is the president, CEO, and founder of DisplayMate Technologies, a gold standard toolkit among manufacturers and display reviewers, CNET included. Holding a doctorate in theoretical physics, Soneira has spent 23 years fine-tuning the algorithms that analyze visual data on screens of all sizes, from smartphones to TVs. Mathematical models are a specialty of his; in past positions, Soneira has developed intricate tests for both AT&T Bell Labs and CBS (CNET's parent company), among others.

This mountain of experience and expertise is why I'm paying attention when Soneira tells me quite plainly over the phone, "Just about every single spec on displays is exaggerated."

And by "exaggerated," he suggests skewed, misleading, and sometimes utterly useless. Why? Because while a screen's resolution and other specs can indicate a certain level of performance, there are many more factors involved in determining a display's actual level of performance. … Read more

Just days ago, Samsung announced the Samsung Galaxy S III, the global, quad-core, Android Ice Cream Sandwich successor to its best-selling smartphone ever, the Galaxy S II.

CNET readers' reactions were mixed, with several comments that the 8-megapixel camera didn't seem too hot.

Rumors of a 12-megapixel camera leading up to the announcement were partly to blame. It's no wonder that some felt that a perfectly good 8-megapixel spec was taking a step back, especially with the 16-megapixel shooter on the HTC Titan II out in the wild, and Nokia's 41-megapixel 808 PureView, a Mobile World Congress … Read more

Apple has officially started selling an unlocked iPhone 4.

The company's online store now lists both a 16GB and 32GB unlocked version of the smartphone. Customers can choose between a black or white model. The company's 16GB version retails for $649, while the 32GB option is available for $749.

Apple currently sells locked versions of the iPhone for $199 and $299 for the 16GB and 32GB models, respectively.

"If you don't want a multiyear service contract or if you prefer to use a local carrier when traveling abroad, the unlocked iPhone 4 is the best choice,&… Read more