What can I add (besides caramel) to my frap for flavoring

Basically ANYTHING you want. Seasonal fruit(made into purée). You seem to like caramel, then try to add butterscotch sauce to it, for a little twist. From fruit, to chocolate sauce, vanilla essence, any essence of any sort(almond/rosewater...)

You could make a sugar syrup with vanilla beans. Leave the beans in there for a more concentrated flavour. Then add a dash whenever you want something smooth and sweet. It's also great with espresso, ice and ice cold milk :)

Crushed cookies, like oreo or thin mints.

"Frappe" is the Boston word for milk shake. You can add whatever flavor or fruit you wish to make it taste just the way you'd like.

Spices:Cardamom, cinnamon, nutmeg
Cocoa powder or melted chocolate