The GSM family of networks, or Global System for Mobile Communications, is the most popular standard for wireless technology in the world with 3 billion users (41 percent of the population).

The GSMA, an industry group, reports an 86 per cent market share worldwide which translates into important advantages: callers get international "global" roaming so they can use their same phone number and device while traveling anywhere in the world-219 countries support GSM international roaming.

Because of this large market, there are more cell phone options from which to choose.