My sister is addicted to having the internet on her phone. It's gotten to where she'd rather mess with her phone than interact with the family when she's home. It's irritating. I finally told her I wasn't going to catch her up on a TV show if she missed something because she was busy texting or whatever. I'm just not going to do it. She starts doing that if we're talking or hanging out and it's rude as hell and I get tired of it.
They do have their advantages, certainly, and I wouldn't want to give mine up, but I do try to be mannerly about using it, and make sure I'm not ignoring people in favor of my phone.