I do remember when SMS where actually free in Germany (where customarily telecoms charge you an arm & a leg). This led to people carrying mobile phones (era before smart phones), but only ever used SMS. You've seen them 'simsen' in bars, coffee shops, everywhere. Looked quite funny then (even though we appreciated that they stopped talking loudly on their phones all the time everywhere). I still can't quite get used to the view of people with a screen glued to their face.