Generally, we use 3G/4G services to ensure the Internet connection anytime anywhere, but the things will go different when we are travelling abroad to avoid the expensive international roaming charge, we may consider purchasing the local 3G/4G services.
If your destination is China, then the following information may be helpful for you.
1.
Choosing a carrier There are 3 carriers providing 3G services in China, namely, China Mobile which owns the TD-SCDMA/TD-LTE network, China Union which owns the WCDMA/FDD-LTE network, and China Telecom which owns the EVDO/CDMA2000.
As TD-SCDMA is rarely applied outside China, your devices may not support this mode.
So, you can just forget it.
WCDMA/FDD-LTE is the most widely used system in the world.
If you come from North America or Europe, it will certainly be possible for you to use the WCDMA provided by China Union.
EVDO/CDMA2000 is another widely used system which is accessible by operators of some countries, so you may also take the China Telecom into consideration.
2.
About the roaming charge It will charges the roaming cost of trans-provincial communication in China, so you have to pay special attention whether the 3G/4G data SIM card you bought is a nationwide one or regional one.
If you haven't given a special statement, it will be likely for you to buy the regional card rather than a nationwide one.
The latter is a litter more expensive, but it can save a lot of roaming charges for you if you are taking a trans-provincial trip.
3.
Charging way There are two charging ways for 3G SIM cards for network visit: by time duration and by data volume.
The former way is usually privileged for contracted clients, and it is not suitable for short-term stays, while the latter way generally takes GB as the unit, and its period of validity can last from one month to a year.
4.
Purchase ways There are 3 approaches to buy 3G SIM cards: service halls of the carrier, retail stores and online ordering.
There aren't many service halls of the carrier, and you have to wait for a long time to get the service.
It is relatively convenient to buy from a retail store, but you still have to go to the service hall of the operator for registration and activation before using the SIM card due to the real-name system requirement for mobile communication in China.
These two approaches are suitable for natives.
However, for short-term visitors, online ordering and purchasing is probably the fastest way.
The SIM card bought in this way has already been registered by the retailer, so that you can use it directly on receiving the SIM card.
While having an international trip, our destination is usually somewhere strange, and the language difference may lead to some difficulties in buying services by us.
However, these may happen only after we've found the service provider in the strange environment.
Therefore, it is the most convenient and efficient way to buy a card in advance online when possible.
Such service is easy to be found on the internet via search engines, and abundant information and sufficient time can be available for you to compare the products and make a choice.
Just like booking hotels and flight tickets, ordering the network service can also be part of your preparation for the trip.