The fan experience takes center stage at music and arts festival Bonnaroo. The event based in Manchester, TN, hosts 80,000 attendees, according to Bonnaroo’s website, and these patrons have a significant economic impact during the four-day festival. According to a study conducted by Bonnaroo and economic development consultancy Greyhill Advisors, festival-goers contributed more than $50 million to the city and statewide economies in 2012. So every year Bonnaroo is pressured to put on a stellar customer experience performance that convinces patrons to return.

However, each attendee marches to the beat of his own drum, and knowing how every patron experiences the 700-acre festival can be a challenge. For the past five years, Bonnaroo relied on radio frequency identification (RFID) technology, like tracking wristbands, to monitor how attendees wandered throughout the festival. Bonnaroo obtained insights from the technology early on: After using RFID devices for a year, Bonnaroo discovered that about 20,000 attendees weren’t enjoying the festival from Centeroo—the main hub of the “musical utopia” where attendees can check out performances and vendors, explains Jeff Cuellar, VP of strategic partnerships for AC Entertainment—the cofounder, owner, and producer of Bonnaroo. To better understand where and how these attendees were experiencing the festival, Bonnaroo worked with mobile app developer Aloompa to deploy iBeacons throughout the grounds for its most recent festival this past June.

“We wanted to see what data we could get out of it…[and] how we can take our event forward and provide more options and things [to provide] a deeper experience for [Bonnaroo’s] fans,” Cuellar says.

iBeacons are small, wireless devices that send targeted communications to iOS users who are within a certain proximity of them. Bonnaroo implemented more than 110 of these devices throughout its festival grounds and camp site (where about 95 to 96% attendees stay during the event, according to Cuellar) to track where attendees went, at what time they went there, and how long they stayed. Bonnaroo could only track attendees who downloaded the festival app and gave the brand permission to send geo-targeted push notifications; however, Bonnaroo didn’t identify these users on a personal level. The festival then monitored their travels through real-time heat mapping.

Although the majority of iBeacons solely tracked data, some of the devices sent push notifications about nearby attractions or amenities. For example, if patrons walked by one of Bonnaroo’s water fountains, the brand sent them a message reminding them to stay hydrated, Cuellar explained. Or, if guests passed the festival’s emergency services, Bonnaroo would send a notification advising them to visit the medical staff if they’re not feeling well. To avoid coming off as intrusive, Bonnaroo implemented a few censor restrictions. For instance, if a patron walked passed an iBeacon, realized that he was going the wrong way, and passed it again, Bonnaroo would only send him one push notification, Cuellar says. In addition, if an attendee passed an iBeacon and didn’t have a phone signal, Bonnaroo would cancel the push notification to prevent it from popping up in an irrelevant context later on.

Cuellar relates these iBeacons to a mobile information booth and says that they enabled guests to discover new festival features.