China Mobile Phones:
If you can use your mobile in China it probably only allows you to call home and can not be used to make local calls, so check payment rates before you leave. It may be cheaper to call home using an IP card that you can easily buy locally.
The Chinese GSM system uses 900 MHz and 1800 MHz, and most phones are sold with only those frequencies. Those phones will work in Europe, South East Asia, and Australia, but not in the US, Canada or South America (1900 or 850 MHz). Consider buying a "world phone" with more frequencies. Examples: Panasonic has some 3-frequency (900/1800/1900) models; Nokia has many three-band models, e.g. 6310i; Motorola has several high-end models with four frequencies, camera and other extras, e.g. RAZR V3 which is about ￥1500 in China as of early 2007. These and other brands are all available in China, but often slightly cheaper in Hong Kong (Hong Kong uses both 900 and 1800 MHz instead of 900Mhz only in mainland China).
China SIM Card:
Chinese phones, unlike those sold in many Western countries, are never "locked". They will work with any SIM card you put in them, not just cards from one vendor.
While buying the SIM cards and calling cards is not an easy thing for the foreigners if he can not speak Chinese, and also for recharging your airtime for your SIM card. Now there is still a company PandaPhone China wireless service provider will solve your communication problems in your China trip, which specializes in China Cell Phone & BlackBerry Rental, China SIM card services and Airtime Recharge services for the foreign people.
The country dialing code for mainland China is 86. Hong Kong, Macau and Taiwan have their own separate country dialing codes which are 852 for Hong Kong, 853 for Macau and 886 for Taiwan.
Internet bars in Beijing are common but hard to find although most hotels and hotels offer an internet connection costing about 10 Yuan per hour.
The fastest, free, in-room dial-up service is 95962 (user name and password 263).
For save the costs, there are two types of widely available and the simplest and cheapest methods:
To use a public telephone you'll need an IC (Integrated Circuit) card available from post offices, convenience stores and street stalls, in values beginning at 20 Yuan. A brief local call is typically 0.30 to 0.50 Yuan. Phones will show you the value remaining on the card when you insert it, and count down as you talk.（If using a public phone, you'll need an IC card to make the initial local call because phone boxes don't accept cash.） Forget about taking access numbers with you - you can call internationally for a fraction of the cost using an IP (Internet Protocol) card, available wherever you see the letters 'IP'. Depending on where you call, a 50 Yuan IP card can give you about an hour of talk time.
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