Taylor Swift joined by Kendall and Cara on stage in London

Taylor Swift invited a bunch of her famous friends on stage in London to make an "unforgettable" end to the UK leg of her 1989 world tour.

Kendall Jenner was at Hyde Park before heading to Glastonbury to watch her sister Kim's husband, Kanye West.

Karlie Kloss and Cara Delevingne were also at Taylor's British Summer Time gig.

Wearing coordinating black and white outfits, her friends walked down a stage runway as Taylor performed Style.

Tweet by Taylor Swift showing photo of her and her friends on stage

Introducing "Serena Williams from Wimbledon", Taylor also brought out her friend Gigi Hadid, while Cara Delevingne waved a giant union jack for the occasion.

Taylor then asked the crowd to bounce and wave their arms in the air so her friends could experience the view she gets on tour each night.

Tweet by Gigi Hadid showing photo of Taylor Swift and friends

"I've said this before," she explained.

"There is no summer crowd like a London summer crowd."

Taylor Swift spoke a lot about what friendship means to her throughout the two-hour show.

"My definition of friendship has two requirements," Taylor said.

"You have to like me and you have to want to spend time with me.

"So I guess the reason I'm so happy right now is I'm hanging out with 65,000 friends in Hyde Park."

Everyone in the audience got one of Taylor's life-saving wristbands, blinking all the colours of the rainbow as they lit up the London sky at Hyde Park in time to her music.

Last month after a Taylor gig in Louisiana, USA, three fans were rescued from a car crash when another driver spotted the flashing lights on their wristbands.

In London, fans Sam Bird and Meg Brien from Hampshire told us about a lucky chance encounter with Taylor Swift's mum, who escorted them to a better position in the crowd.

"We were right at the back and Taylor's mum found us," said 24-year-old Sam.

"She was like, 'I'm from America, I'm Taylor's mum and I see your colours and your dancing and we want you at the front.'"

Fans Meg and Sam say they were escorted to a better spot in the crowd by Taylor's mum

"I thought it was a trick," admitted 21-year-old Meg.

"I didn't believe it and now we're here and we got the best view ever."

Taylor showed off an impressive range of stage outfits, along with an equally impressive range of coordinating microphones, from a diamond-studded mic, to one embellished with her 1989 logo and another one that glittered gold.

There were a number of instrument changes throughout the night for Taylor as well, from a handful of guitars, to a keyboard, and ending with a "weird looking space piano" as she called it.

Her set began with Welcome to New York and included most of the songs from her 1989 album, along with an updated Love Story and an angry rock take on We Are Never Ever Getting Back Together.

Taylor Swift had also gone to the trouble of having her touring hydraulic stage fitted into Hyde Park, allowing her to be raised high above the crowd throughout the evening.

It had the added bonus of giving some of the younger members of the audience a better view of their idol.

Like many others, 10-year-old Aisling from Eastbourne, 9-year-old Isabella from Essex and 11-year-old Megan from London had decorated their arms and faces with Taylor lyrics.

"Yesterday I made a poster and so did Megan," Aisling told Newsbeat.

"I researched on the internet that Taylor's favourite colours are red, white, navy blue and purple so I put all those plus more on my poster."

Aisling, Isabelle and Megan had made posters for the Taylor Swift gig

Rae Morris set the pace for the day, opening the stage in the middle of the afternoon, serenading the early crowd with songs including Love Again and Under the Shadows.

"Everybody is a massive Taylor fan in some way I think," Rae said.

"I think she's just doing it her own way and I think in this day and age we all want to see real people and she is being really real.

"I think for young girls that's an incredible role model to have, somebody who is just breaking the rules and just doing her own thing."

Rae Morris opened the stage

Rae was also impressed by Taylor's recent standoff with Apple Music, when Taylor withheld her 1989 album from the new streaming site until Apple changed its mind over paying royalties during an initial three-month trial period.

"I thought it was really interesting," Rae said.

"And I thought it was amazing that she actually spoke out and it's incredible that someone in her position would speak out and she did right, it was really good."

As you'd expect, the entire line-up had some kind of connection to Taylor Swift, from her mate Ellie Goulding, to John Newman, who by his own admission is "very good friends with her boyfriend".

John Newman featured on Calvin Harris's track Blame which reached number one in the official UK singles chart last September.

John Newman was "a little bit star-struck" the first time he met Taylor

Despite being a "little bit star-struck" the first time they met, John thinks it's simple why Taylor Swift is such a big star right now.

"Because she works very, very, very hard," he said.

"And she's genuinely a very nice person, she's got no ego."

Vance Joy is 13 shows into his support slot on Taylor Swift's 1989 world tour, with another 62 still to go.

Taylor covered his track Riptide in Radio 1's Live Lounge in October 2014.

"She did a fantastic job and I was totally flattered," Vance Joy said.

Vance Joy is supporting Taylor on her world tour

"Now I'm 13 shows in with her and I've learnt a lot about performing from watching her.

"She's super composed and gives a lot of herself every night, she's super poised."

He doesn't know if he's made it into Taylor's inner circle quite yet, but is confident that he's "in one of the circles".

They hung out after a gig in Pittsburgh recently that ended up with a guitar being passed around between Taylor Swift, Vance Joy and some other bands that had been on stage.

"We sang Blink 182," Vance Joy recalled, "and we all didn't know the lyrics to What's My Age Again?"

Emma Watson, Mollie King from the Saturdays and Fifty Shades of Grey star Jamie Dornan were among Taylor's famous fans on the London guest list, along with three Spice Girls - Mel C, Emma Bunton and Geri Halliwell.

Sunday is a day off from touring for Taylor before her 1989 show moves on to Dublin on Monday.

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