Group3 is telecommunications provider established in 2001 HQ in Markham, ON. Group3 main focus is to provide wholesale VoIP termination services; what that means is their main market is one of the long-distance providers who buy in bulk calling routes (or termination).
Though Group3 does offer a Home Phone plan, worldwide calling with some of the usual features such as porting your home phone number and caller id. Also, Group3 does support SIP Client so one could use clients such as SIP Droid on a Smartphone or X-Lite.
Unfortunately, we were not able to verify calling rates - Group3's website is not fully functional in that allows seeing the rates. Though considering you are getting worldwide calling may not be an issue.
With all said, Group3 could be an option to consider though we prefer those providers that disclose all information. We could not check how many minutes are included either.