That’s very smart, so try to lead by example. When you are together be the leader and ask that all phones be turned off so no one interrupts your family get together. If you are visiting with them and he keeps looking at the phone or the phone goes off you might remark “Oh Chaim, the phone again, I was so hoping to enjoy your company for just a short uninterrupted time, is it something very important?” Try to make him feel important and wanted instead of criticizing him about his habit. Try involving him and including him to keep him busy and interested in what’s going on. Make a point of telling your husband, “Tatty, let the machine get it, don’t answer the phone when the kids are here, we can call who ever it is back when the kids leave”.
These are important teaching tools that you are role modeling for them.