Criminal gangs and thieves at Liam Gallagher's Cardiff concert on Wednesday will be targeted using newly-fitted facial recognition cameras.
South Wales Police has fitted cameras in the foyer of the Motorpoint Arena.
They were first used at Kasabian's gig on 4 December and organisers said no phones were reported lost or stolen, down from about 20 at previous shows.
Insp Simon Davies said groups of criminals go to concerts "with the sole intention" of stealing mobile phones.
Cameras will scan the faces of people entering the gig and check them against a database of suspected thieves and pickpockets across the UK.
Suspects will be detained by the venue's security team or arrested by police.
There are two fixed cameras, but they are only turned on for certain concerts or events when police and the arena think it is necessary.
The cameras do not work unless they are connected to a police van outside which has the facial recognition software programmes.
At the Kasabian concert, two men from London were issued with a notice banning them from Cardiff city centre for 48 hours.
Another, a 22-year-old from London, was arrested on suspicion of going equipped to steal after being found wearing a woman's swimming costume under his clothes and carrying a small tool used to remove Sim cards from iPhones.
Insp Davies said: "We know there are groups of criminals who travel to concert venues, including those here in Cardiff, with the sole intention of stealing mobile phones.
"We are really pleased to be working with the arena to keep Cardiff safe in this way and hopefully send a message to criminals who think they can come here for rich pickings."