This is a problem that we are hearing more and more about. Whether from Greece, as you are, or from the U.S., or from other corners of the world, people are upset about partners and family members who would rather talk to someone on the phone than to the person sitting in the same room. The etiquette for the new technology is still being developed. We don’t have a common understanding of what is and is not OK phone behavior.
You can’t make your wife stop using the phone. What you can do is tell her that you miss having time with her and that you miss the conversations you used to have with her. Instead of telling her she is doing something wrong, ask her if she could please set aside some times of the day when she can be with you. Reassure her that you aren’t trying to control her or tell her who she can talk to. Focus instead on how much you love her and want to be with her. Then see if the two of you can set some times when she will turn the phone off and turn her attention to you. Of course, your end in this is to do what you can to be an interesting and interested partner.
I wish you well.