To my Coachellagoers we officially have one week! So this post if for my fellow milk shake lovers. Sonic is starting a new campaign where they target millennials, where better to do that than a music festival? If you have the Sonic Drive In app or check your sponsored Instagram post during the festival you can actually order these square milkshakes and have them delivered to you by using a geo fence! The best part is you pay by posting a pic on your Instagram so basically it's free. Check out this video of Christine Flynn talking about the milkshakes.