The newer version 2 of the app adds the texting feature and allows the sending and receiving texts (SMS) to and from US and Canada mobile phones over Wi-Fi or mobile data at much lower rates than regular SMS sent and received over the roaming network.
The app does not require having a OneSimCard SIM installed in the phone, but it does require having a OneSimCard account and a VOIP and SMS enabled PEN.
Initial settings for the app are available in the “My SIM Cards” menu of the OneSimCard online account. When in the My SIM Cards menu, select the SIM (if there are more than one on your account) and then click on the Create VoIP Account link. This will create a OneSimCard VoIP account and provide you with a link with Settings information for your phone.
Important: Connection quality of the calls made using OneSim VoIP option over the Internet will only be as good as the quality of the Internet connection. Please be advised that in many cases this kind of connection quality is inferior to the connection quality made through the OneSimCard international SIM card roaming network.