After spending the summer at coding camp, Allie Navarro can't wait to share the app she built with her friends. Based on an algorithm she created, the Best Friend Finder (AKA the BFF) matches people up with others and ranks them according to best friendship potential-except it doesn't reveal who your match is until you get close to them, transforming the user experience into a real-life scavenger hunt. Allie is really proud of her app, and it has even been entered in an upcoming coding competition But when a glitch in the BFF causes unexpected drama among her friends, Allie knows she has to do something to fix her app. So Allie reluctantly pairs up with Nathan, another coder and her sort-of-enemy who is struggling to build a game of his own for the coding competition. Except they can't stop butting heads long enough to help each other out, which they'll have to do if they want any chance at winning. But as tensions escalate between Allie, her friends, and the rest of the students in the school over drama created by the BFF, she'll have to decide if her app is really worth fixing.