wpadać z wizytą in English:

Why don’t you drop in for coffee some time?

if you are in the neighbourhood, please drop in

If you're in town next month, we'd love to see you. Please try to drop in.

You can drop in tomorrow in the afternoon.

Among the many delights of Christmas Eve in Poland is the custom of setting an empty place for an unexpected friend, relative or stranger who happens to drop in.

If you are in NY some day, don't forget to drop in.