Both Acrobits Softphone and Groundwire are capable of making calls over 3G/Edge networks. Unfortunately, many cellular providers still either intentionally block or simply mishandle SIP traffic. While we can't guarantee that our clients will work over every 3G network, there are certain steps you can take if you have any issues making calls over 3G networks. Depending on the nature of the issue, check out one of the articles below.
If you can register, but have audio issues when making calls,
no outgoing audio
https://faq.acrobits.net/no-outgoing-audio
no incoming audio
https://faq.acrobits.net/no-incoming-audio#
no audio in either direction
https://faq.acrobits.net/no-incoming-audio#