Depends on the country. In Poland, most banks use a standardized interbank instant cheque system which is integrated with your phone number, and everyone would

Depends on the country. In Poland, most banks use a standardized interbank instant cheque system which is integrated with your phone number, and everyone would use that for settling small sums between each other. Sweden has a similar system that's even more flexible. Meanwhile, German banks offer a similar solution (giropay), yet - in this privacy-obsessed society - everyone uses PayPal instead.