A SIP line allows you to call and receive calls anywhere in the world via Internet at a profitable rate. Check the french provider OVH pricelist (here).
You can singup for an SIP OVH line (here) for 1.19 € / month.
Zoiper
Once you have your username and password, you can install Zoiper on Android from the Play Store (here).
Open Zoiper in your apps:
Select Agree...:
Select Skip at the top:
Select Yes:
Enter your username and password (keep this format with @) and select Create an Account:
Select Next:
Select Skip:
You should see SIP UDP with green Found label. If not your username/password must be wrong. Select Finish:
Select Allow:
Allow Do Not Disturb access:
Turn on contact permission:
Try to call someone using your contacts list in Zoiper or dialing a number:
When you finished, you should Exit the app if you don’t want to receive incoming calls:
