I find it annoying. If I was talking to someone and all their attention is on their phones, then I'll excuse myself and tell that person seeing that they are so busy, I'd rather do other similarly important things. Of course it might appear like you are an attention-whore but well . . . if someone prefers chatting on the net then it's better that they be left to it.
I personally feel it's very bad etiquette,very rude. If you know that person is a businessman, and they've explained in advance they're waiting on something to come through then that's fine. If a call comes through and they apologise and explain they absolutely have to take the call, that's good manners. But if it happens all through the date, I'd be put off. For me that sets the tone of any potential relationship you may have in the future. There're also people who'll visit you and then sit there checking their Facebook and sending and responding to whatsapp and text messages. I think there's no excuse for that sort of behaviour, they may as well leave.
I don't think that it's rude for a person to check their phone while out with people, however, it can become rude when they always check the phone. I personally do not check my phone because I believe I am long past the days of texting 24/7, but if a message comes on the phone while I'm with someone, I'll check, I'll reply if needs be and I'll put the phone away. It is rude when you are with a person, trying to spark up a conversation, and all you get is a glimpse of their faces every minute for every 10 minutes as they are so preoccupied with texting other friends, it's not only rude, but it's a bad practice.
