Friendships between artists can be important in many ways, from touring companionships to mutual encouragement, but the best time is when they turn into creative collaborations. As part of the Life in Stereo series on music and collaboration, we find out how rapper Little Simz and producer Osiris the God (aka OTG) became friends during a snowstorm on the streets of Prague.

Little Simz fondly recalls the moment when his relationship with OTG really took shape. They were on their first European tour together and had arrived in Prague on a cold winter's day. After the soundcheck, she and OTG went for a walk in the Czech capital. "It was snowing like crazy, it was crazy," Simz recounts today. "The city had an old-school feel, and we'd walk the streets, making snow angels, it was a real memory, lost in Prague. Time would go by, we'd literally have a concert, the doors would be open, and we'd be nowhere."

Fortunately, they got back in time and the show went off perfectly. It was the first triumph of a collaboration that has flourished both in the studio and on stage, from its E.D.G.E. project in 2014 to an appearance on OTG's The Book in 2017. It all began when OTG first heard Simz's music at university and instantly became a fan. "I knew she had a lot of potential," he recalls today. He began e-mailing her his own productions. Busy with her own music, Simz ignored them for months, but when she finally opened one of OTG's messages and listened to it, she realized she'd missed something. "I figured this kid was really sick," she recounts. "I went back and opened all the unopened emails in the past and figured I was sitting on a gold mine. I had no idea! That's when Simz asked OTG to join her on her first European tour.

It took Simz some time to figure out how to integrate collaborators into her music, which she readily admits was "a control issue" due to the fact that the early part of her career was very DIY. Today, she says, "I want their input, and to know if the hook sounds good or if it can be improved" - and this is particularly true where OTG is concerned. "I wrote with Osiris and I don't write with anyone," she says.

Simz and OTG have discovered that the key to making their studio work is knowing when what makes them different can be an asset. According to Simz, the biggest difference between the two is their approach to music creation. She readily admits that she's more concerned with "the feel, capturing the magic, it doesn't have to be a perfect mix", whereas Osiris is obsessed with finding the right sound and, if left to his own devices, would sit for hours making sure it was perfect.

Simz points out that if she were as obsessed with sonic detail as OTG, they'd get nowhere, but it's the combination of her quest for sensation and Osiris's mastery of sound that makes it work. "I need to be 'yo, don't worry about the bass drum, record the pattern, think about how it makes us feel and move,'" explains Simz.

Likewise, both artists readily admit they have differences. "There are a lot of them," says OTG. "I think it's good to disagree with your peers, because it opens you up to perspectives that maybe you've never seen or thought about before, and it really gives you more insight into someone's thought process." Simz agrees that these arguments "make us stronger - if Osiris has pissed me off, or I've pissed him off, he'll let me know and I'll do the same. We feel so comfortable that we can tell each other. So, as well as being artistic collaborators who instinctively understand what the other wants to do, they've become as close friends as it's possible to be. "He asks me about girls, 'what does she mean by that', so we meet on that level too, which is the craziest thing because it's not just music - it's family."

OTG: We had a great time at our friends' party.

Simz: Outside of touring, we hang out a lot, even if he comes to my place where there's a little studio and uses it to make beats or whatever, while I do my thing. He's like a brother, really.

OTG: Certainly, but it's very subjective. People can form their own opinion of a person through their art and unconsciously begin to expect them to be that way. As you can imagine, this can disappoint someone for the wrong reasons.

Simz: Even some of the things he listens to every day, you wouldn't think he listens to. He's a real musician, isn't he, so when he hears things, he sees what he can do in terms of sampling. His palette is just open. He's very experienced.

OTG: Honestly, I can't answer that question, there are too many memories running through my head. It's impossible to choose one.

Simz: Definitely Prague. Shared moments deepen collaboration, and we've had so many moments like that. Even when I come back and tell my other friends about it, all they can say is "oh, that happened, yes", but only Osiris and I will know how funny it was... or scary.

Simz: I like the attitude of Londoners. We're just moving on, aren't we? We're very lively in a way. I could go into so many different scenarios and it would be like a movie. I don't seem to find that anywhere else in the world.

OTG: London is very important to me, because it's where I was born and raised. It will always be a part of me by default. I always feel that people who come to London from other countries are surprised by what they discover. It's not all tea and crumpets here, there's a lot of culture to explore.

OTG: All the time.

Simz: Yeah, he sure gives good advice. He's a boy, you know what I mean. I've had relationships with boys and sometimes I don't understand you, but Osiris breaks things down to make sense, and vice versa.

OTG: Absolutely. When you're on the road, as well as working together, you practically live together. So it's important to have a good balance between friendship and work.

Simz: Yes, of course. If I feel like I don't want to do this show or whatever, but Osiris is there, that makes a difference.

OTG: I wouldn't say it's too different. At the end of the day, it all depends on the type of people involved.

Simz: I think that's a good thing, why wouldn't you want to have a close friendship with someone you make music with? Anyway, it takes the pressure off. If I feel I'm not in the right frame of mind to execute what we have to do, I know there's no judgment, it's "yeah cool". It's so easy.

OTG: If money were no object, we'd take a trip into space.

Simz: It would definitely have to do with food. We're always showing each other amazing places, I try something and think "Osiris will love this".

Simz: He's done a lot of things. We've had some very emotional discussions, we've both cried.

Simz: He's very caring.

Simz: He's always ready to order food or eat. I'm also on his Deliveroo account, so when I order and think I'm being sneaky, he says "so-and-so is on his way yeah" and I'm dying with envy.

Simz: I think Hiatus was a good one.

AUTHOR LUKE TURNER PHOTOGRAPHER WILL ROBSON-SCOTT