Siphon is a SIP/VoIP client for the iPhone and iPod Touch 2 that allows you to save money on calls when Wi-Fi coverage is available. You can enable VoIP on 3G/GSM, if your carrier subscription allows it.Siphon SIP/VoIP project is the first in his category that works on iPhone and iPod Touch 2 with headset for all SIP providers. It is a native application approved running on 2.X using internal micro/speaker and headset.
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