When my mom was visiting me not long ago, she had to call her neighbor in Europe to check something. I gave her my tmobile cell phone and she called for about 10 minutes. The next billing cycle I was hit with $60 one call fee! I was furious. Called tmobile customer service and inquired about it. My plan clearly states 25 cents to international locations. The customer rep told me that the call that was made was to landline not mobile network! I've asked to be transfer to her supervisor, explained to the guy what had happened and he removed the charge. All those mobile providers play dirty games.
Before I had $10 a month unlimited calls to Europe (landlines and cell phones), since I was able to teach my parents how to use iPad with FaceTime I was able to cancel that add on to my plan. Now I think it cost $15/mo.
Also, all of my customers in Europe, ME, South America and Asia use WhatsApp to call me. I don't remember when was the last time that someone has called me on my actual cell phone number. They don't want to pay and I don't want to pay