Hello,
when you log in, you'll get a cryptic Passwort for SIP Operations.
Your username is the Liechtenstein Mobilenumber without 423 eg. 661xxxxxx
The Setup-Procedure is explained in the FAQ session.
Mr. Rupf was former CFO of United-Mobile.
I tested the SIP feature with my Speedport W700V Router (delivered by Deutsche Telekom)
I received calls only when calling my US-number, then the mobile phone kept quiet. (Mobile phone was registered in German E-Plus radio-network) When I switched off the VoIP-Account in the router, the mobile phone rang again.
When the "VoIP-Telephone" rang and I lifted the receiver I heard nearly nothing of the callers party and they didn't hear me, sounded like to less bits for decoding my voice.
I could not make outgoing calls via SIP. I didn't find out, which area codes are necessary, as I do not know, how and where the SIP-Server is connected to the PSTN, if he is. (Liechtenstein, Germany, US, anywhere?)
To be honest: I'm not so familiar with VoIP-Things, so I do not know, if I did all setups correctly.
But lets keep realistic. How should their business modell work, if callers could reach the mobile via SIP for free?
I think, to answer all this questions, you should invest in your own SIM-card
