Dunkin Donuts running (NYC Metro area) is running three promotions which automatically stack.
Medium Iced Coffee for 1.99 (normally 2.99).
Order on the app for pickup and 3X points (only coffee, not lattes)
Opt into Auto Reload and 2X points
Net result is that $2 iced coffee gets you 40 points. 200 points equals a free drink which can be used on any drink including the $5 specialty drinks.
