BlackBerry SIP VOIP softPhone, open source SIP client, SIP stack
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1) VoipSwitch
Blackberry dialer 价格20$
试用版本：Demo version has limited call duration to 60 seconds, and doesn’t require activation code.
http://voipswitch.com/en/products/softphones/mobile-softphones/softphone-for-blackberry/
SIP软电话：安全呼叫，支持iOS, Android, BlackBerry, Symbian, Windows Phone
http://www.mobileasiaexpo.cn/2012-sponsors/
该公司还提供
a)“多门户视频” Video MultiPortal
b)高品质视频通话(iOS, Android)
c)VoipSwitch软交换硬件
d)VoipSwitch软交换hosted service，Join Express - VOIP Client for VoipSwitch's hosted service http://www.voiceserve.net/
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2)Linphone 开源的
绑定VOIP服务的客户端，通常客户端免费，服务收费
在BlackBerry App World中搜索VOIP即可
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SIP Stack
pjsip
pjsip support for BlackBerry 10
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