People posted all over Facebook about phones being stolen during the festival, with someone saying 28 phones had been stolen with some being traced to Bury, Rochdale, Blackpool and other areas.
Barry McLeod’s daughter Molly, 17, a sixth former at Lancaster Royal Grammar School, had her phone stolen at the festival.
Barry McLeod said: “A large number of phones with bank cards, driving licences and other personal items were stolen during the Highest Point music festival on Friday evening - our daughter who attended the event was one of the broken hearted fans affected.
"My daughter had her phone in her back pocket and she said one minute she could feel it there and the next minute it was gone.
"It was the end of term for the sixth formers and it was a leaving gig which they had been looking forward to for four or five months.
"Molly did Find my phone and tracked it all the way through the park and then onto Wyresdale Road near Animal Care then it stopped in Bury.
"We managed to get another phone sorted but it cost us nearly £400. It’s just maddening.
"You’ve got people out there preying on young festivalgoers at an end of term music festival, full of delight and happiness and yet they are left devastated because someone has nicked their phone. It’s so annoying.”
Organisers said 35,000 people attended the festival at the weekend.
They also said they had 150 mobile phones handed into lost property along with driver’s licences, keys, hats and medical items.
Highest Point boss Richard Dyer said: “We have 500 items in lost property and spend a lot of time logging and reuniting people with their lost items.”
If you think you might have lost your phone at Highest Point, email [email protected]
A spokesman for Lancashire Police said: “The festival was attended by thousands of people but we have only had 15 reports of mobile phones being stolen or going missing over the three nights of the event. I would encourage people to come forward and contact police if their phone has been stolen.”
Contact police on 101.