Evaluating free Android version and it seems to work well over LTE.
The SIP provider I use for one of the accounts is bare bones -- you can make and receive calls but, no frills (including no voice mail).
I read somewhere that ZoiPer has call forwarding functionality. However, I haven't figured out how to set it up with the Android version.
Can incoming calls be forwarded to another number or SIP URL from the Android version?