Keep Smiling, used as a goodbye term when u mean to put an end to a chat or series scrappings with smbdy, and at the same time don't mean to be the least of rude.
using this term u feel like making a sweet and caring image of urself before the one u feel like meeting some other day online.
jude : so hows ur love life going?
me : dude, u r cool
jude : c'mon tell me. i'm ur good frnd...
me : my love life. hmmm...
me : i luv ur smile.KS.