If there is no wifi available it, it runs on either Sprint or T-Mobile, whichever has the stronger signal.

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With CDMA technology, data and voice packets are separated using codes and then transmitted using a wide frequency range. Since more space is often allocated for data with CDMA, this standard became attractive for 3G high-speed mobile Internet use.

The CDMA standard was originally designed by Qualcomm in the U.S. and is primarily used in the U.S. and portions of Asia by other carriers. Sprint, Virgin Mobile and Verizon Wireless use CDMA while T-Mobile and AT&T use GSM.

While CDMA and GSM compete head on in terms of higher bandwidth speed (i.e. for surfing the mobile Web), GSM has more complete global coverage due to roaming and international roaming contracts.

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