I need a simple android voip softphone.
At app first page, user need enter user name and password.
Then the app will register sip on background.
We use sip domain and port.
This is a simple app. No super features needed.
I prefer budget under 100 USD as there are many sdk/opensource for that app like sipdroid, sipdialer, csipsimple.
You can easily edit it.
Why I don't use these apps? I don't want end users confuse by setting the configurations. We wil integrate our sip settings in the app. So no need configurations for users.
That app must able to use by wifi, 3G, EDGE, GPRS and so on.