One of the most marvellous things about the music industry of today is a budding artist can notch up millions upon millions of streams without even being a household name.

They can also secure an eye-watering number of fans without having released an album or being attached to a major record label.

As many young artists will insist, it's all about connecting with and building up a core fanbase while honing your craft, getting ready to burst into the mainstream with an almost inexplicable breadth of success already under your belt.

That's exactly what American singer-songwriter and record producer Ari Leff - best known by his stage name Lauv - has done.

Sure, this alt-pop up-and-comer may not be on your radar just yet but the 24-year-old has already become one of the first independent artists to gain more than one billion streams online.

He's also supported Ed Sheeran on tour and topped Billboard's Emerging Artists chart in America for several weeks last summer.

To put it simply, he should probably be at the top of your "ones to watch" list for this year.

But Leff is still somewhat perplexed by some of his triumphs so far.

"Seeing all the streaming numbers, not to sound not thankful but that doesn't really..." he starts, before adding: "Like, when people ask me how does it feel to have a billion streams?

"To be totally honest, that itself doesn't really feel like anything, as opposed to when I actually go to those places and learn that places like Singapore and territories I'd never imagined ever going to were, early on, my biggest streaming territories.

"And then showing up to those places for the first time and playing for crowds of a couple of thousand or whatever. That's when you realise that people are really connecting.

"Or when, after a year and a half of touring, people start coming up to me with my lyrics tattooed on them. It's stuff like that where it's like, 'OK, this is actually real.'"

Leff, a New York University music technology graduate, has more than 16 million monthly listeners on Spotify tuning in to listen to his take on electronic-tinged pop and his guitar and piano-backed ballads, as well as more than one million YouTube subscribers.

The artist, who has his own label, released breakout single I Like Me Better in May 2017.

It's easily his biggest hit so far, peaking at number two on the Billboard Adult Top 40 chart.

Leff admits it's an "odd feeling" being idolised, as he "never really idolised any artist particularly" himself in his younger years.

But who did inspire him? How did this whole music thing become his life? And, most importantly, how would he describe his music, for those not yet in the know?

Leff, with a laugh, says: "That's funny because I feel like, genre-wise, I don't know.

"The best way I would describe myself is that I'm a modern version of a singer-songwriter.

"At the core of my music is just classic songs but now, instead of just guitar and piano, it could be a variety of different styles of production using my laptop."

He ponders for a moment, then adds: "So, I guess, a slightly soulful singer-songwriter?"

Inspired by artists such as John Mayer, Chris Martin and Paul Simon, Leff says from a young age "music slowly became the only thing I ever really wanted to do".

He was "obsessed" with skateboarding as a kid but realised he "didn't have the balls to get good enough" to do it professionally.

"I slowly stopped skating and around the same time I started to play in bands and I had played a few different instruments growing up but once I started playing guitar, that was just my place to explore and express myself in my own little ways," he says.

Despite clearly having a musical knack, Leff reckons his success is more about how hard he has worked rather than a natural gift.

Asked when he realised he was skilled musically, he becomes a bit coy.

"Never, to be honest," he replies.

"When I started singing I was horrible. There are videos of me singing at summer camp and I was so bad.

"I had one band where my friend's dad was like, 'You have to get a new singer' and at the time I acted like it didn't impact me.

"But it was definitely a thing that drove me to keep singing and figuring out what my voice was going to be.

"I don't consider myself a great singer, a great songwriter, a great producer. But I consider myself to have worked really, really hard in all those crafts."

Leff, who recently dropped new single There's No Way featuring his girlfriend Julia Michaels, has promised a debut album in 2019 after he released playlist I Met You When I Was 18 in 2018.

He acknowledges he's rather lucky to be able to unveil music this way, without a demanding record label looming over him.

"We're in a world where it's very 'in the moment'," he says.

"Fans want to feel connected to the artist that they love so it's a more exciting time than ever to be an artist and to be able to release stuff however you want to do it."

Leff is at that glorious point of having hit so many career highs already while still being able to create the music he wants, but not yet being so famous that the celebrity side of things is taking over his life.

On being recognised by members of the public, Leff chuckles: "It's not like I walk out and it's like I'm Justin Bieber.

"It's definitely far from that but it's been kind of weird. Sometimes I'll just be walking through an airport and somebody will stop me so we'll see how that goes."

Looking ahead, Leff says he tries not to let himself be driven by things like getting platinum records or selling out big venues, and that it is "just about the music".

He of course recognises that those accolades, of which he already has a few, are a great byproduct but he insists he is focused on trying to leave his mark on the world.

"Some of this probably comes from my family," he explains, before talking about his mother, who inspired his stage name - Lauv means Lion in Latvian, a nod to her heritage.

"My mum works in vaccine research and is essentially trying to cure HIV/Aids, and her whole career has been dedicated to that," he explains.

"I feel like I want to find more ways outside of music, or using the platform of music to do things that are less self-serving.

"I've come to realise that so much of this is obviously all about the artist, all the time, and it gets to the point where that mentality it is not good for the people and the planet.

"Obviously there's a lot going on right now in the world and people don't really have a reason to care because it's not so bad yet that you have to care.

"But for me, in the past few months especially, I've become increasingly aware of, as I work on more music, trying to find ways outside of that to feel like I'm adding something to the world."

Lauv's single There's No Way is available now.