These syncs occur unobtrusively, and don't require any action on the part of the user after the initial setup, nor do syncs incur any extra fees like text-messaging charges.

这些同步都在后台进行，用户进行过初始设置后不再需要进行更改，也不收取额外的信息费。

youdao

"Fifty-fifty is acceptable for simple services like text messaging or callbacks, " he says.

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Rather like text messaging on a mobile phone, data travel over spare network capacity not used by telephone calls.

ECONOMIST: MONITOR

Much of mobile data spending is still on simple features like text messaging, but carriers are banking on a host of data services for future growth.

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