Sure. Americans with close or many international contacts almost certainly use an internet-based chat/voice app with those contacts. That's not a large enough p

Sure. Americans with close or many international contacts almost certainly use an internet-based chat/voice app with those contacts. That's not a large enough percentage than any one messaging app is a viable option for a group chat involving a dozen randomly-selected Americans. Almost every time, one or two of them will steadfastly refuse to install any app and insist on using MMS.