"Believe," out on Tuesday, serves as Bieber's highly anticipated sequel to his debut album "My World 2.0," and has had critics buzzing on whether the teen who first found fame on YouTube is a short-lived phenomenon or a long-term staple in the music industry.

Bieber, 18, has become one of the world's biggest stars, with more than 23 million followers on Twitter and 44 million fans on Facebook, after being discovered at the age of 13.

The singer has grown up in the public eye in the last two years, dating 19-year-old Disney Channel star Selena Gomez, who is referenced in the album's electro-dance track "Beauty and the Beat."

But fame has also brought its downside and the track "Maria" addresses Bieber's most adult scandal to date. Last November, Bieber was hit with allegations from 20-year-old Mariah Yeater who claimed that the singer had fathered a child with her after a brief alleged encounter backstage.

Bieber, who vehemently denied the claims and watched Yeater's lawsuit fall apart, sings "She was schemin'...she was draggin' my name through the dirt," before hitting the chorus with "That ain't my baby, that ain't my girl."

The album's producer Mike Posner, who has his own solo career with hits such as "Please Don't Go," worked with Bieber on the debut single, "Boyfriend".

The result is a slow tempo beat with Bieber softly rapping "If I was your boyfriend, I'd never let you go, I can take you places you ain't never been before." The song, released in March, peaked on the U.S. Billboard Hot 100 singles chart at No. 2.

OLDER BUT STILL YOUNG

While "Boyfriend" reveals an older Bieber in a more intimate setting, Posner said "Believe" wasn't meant to show Bieber all grown up just yet.

"I wanted to make songs that were reflective of who Justin was when I met him in the studio, not when he was 13. We're not trying to grow him up too much because he's not 25, he's 18, but he's a young man that's living life and having fun, and the music reflects that," Posner told Reuters.

Moving away from pop, Bieber fuses electronic dance music with R&B throughout "Believe," specifically in tracks such as the club-friendly "All Around The World," which sees Bieber team up with rapper Ludacris. and "As Long As You Love Me" featuring another rapper, Big Sean.

The singer embraces R&B influences in songs such as the romantic "Catching Feelings," "Right Here" featuring fellow Canadian star Drake, and the Motown-inspired upbeat track "Die In Your Arms."

But there are still some throwbacks to the style that made Bieber famous, such as "Fall," a guitar-based love song, and the pop-driven inspirational title track "Believe."

Bieber's journey to the top has fascinated critics, as the singer has found stardom by harnessing the power of the Internet instead of the Disney or Nickelodeon TV platforms that launched stars such as Britney Spears, Justin Timberlake and the Jonas Brothers.

By the age of 16, Bieber had a chart hit with 2010's "My World 2.0," that spurned the single "Baby", followed by 2011's 3D film "Never Say Never," that documented Bieber's journey to pop culture icon and grossed $98 million at the worldwide box office.

New York Times music writer Jon Caramanica drew similarities between Bieber and Timberlake - the former member of N'Sync who broke out of the boy band mold a decade ago with "Justified" and went on to forge a successful solo career.

Caramanica wrote that Bieber "doesn't have Mr. Timberlake's backbone, or his experience, or his raw talent for that matter." He suggested that the young singer is instead finding inspiration in "perhaps the biggest and most conflicted teen star of all time, Michael Jackson."

While Posner understands the comparisons, he said Bieber wants to establish his own credibility.

"I know Justin doesn't want to copy anyone or follow anyone's footsteps. He's very intent on having his own career and carving his own path," he said.

(Reporting By Piya Sinha-Roy, editing by Jill Serjeant)

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