After years of having to drive into town to place calls, a farmer finally got a phone line installed in his home. A friend was visiting and in the middle of the conversation, the phone rang. The visitor assumed the farmer would answer the phone but he just let it ring. "Why didn't you answer the phone?" The visitor asked. The farmer responded, "I got this phone as a convenience. Right now I'm talking to you and answering the phone would not be convenient."
As an GenXer, I grew up without the internet and a cell phone. They both became popular while I was in college, so I'm very comfortable with it, but remember life without it. (Really, there was!) In the beginning... the cell phone was for emergencies only. (You only had 100 minutes a month anyway.) There was no such thing as texting. People would never answer their phone in the middle of a conversation with a live human being in front of them. And if it was a really urgent call, they would still feel terribly rude if they took it.
If the conversation you are currently having is important and you value the person with whom you are speaking, then that is what you are doing right now. You can call back, the text won't disappear, learn the art of delayed gratification. For the 1% who don't realize this: By answering the call or text, what you are saying is that the person to whom you are speaking is not really that important to you. You have other things to do.
one sec... i just got a text...