What does it mean if your guy friend puts a kiss symbol at the end of a text?

Depends on the rest of the text and how well you know him. He could be a player and you are the prey he is fishing for. Some of these fellows like to send something like that to draw you in. Stay cool. It is possible he likes you. If he is only someone you have met online I would be careful or if you know him from school that is a different question. He is trying to be cute and if you have never met him that raises some warning bells.