从前,我们需要注册一个VOIP提供商,并附加一个美国号码.
For example,
1. register a VOIP provider like discount VOIP.
2. get a US number from IPKall
3. then attached the number to GV
4. Install Android SIP Client to use your VOIP Provider.
The only catch with Sipdroid is that you have to use http://pbxes.org to tunnel your VOIP calls. The service is free, but the set-up is a bit tricky. You can refer to this link.