By Tyler Calder

It’s hard to pinpoint the exact moment when my group chat became an endless loop of astrology memes, but I’m pretty sure it was some time last year – just shortly after Co-Star released its modern, millennial-friendly astrology app. Coincidence? Probably not.

The app’s minimalist interface brings astrology to the masses – making it easier (and ~cooler~) than ever to know your sun sign, your moon sign, and read your natal charts just for fun before bed. We sat down with the company’s CEO and co-founder, Banu Guler, to learn more about the astrology app you just can’t get enough of.

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Can you tell us a little bit about the genesis of Co-Star and how it started?

I’ve been into astrology for a super long time, but kind of assumed it was something that only my wingnut friends and I were into. So, a while back, I showed up at a friend’s baby shower with a full book-length interpretation of the baby’s natal chart designed out to be super goth and dark, meant to alienate people. But, it completely backfired and everyone was like, “Wow, I want to buy one of these.”

I was working in the fashion world and living in Brooklyn. It set a bug in my ear, and I just started paying more attention, noticing how people used astrology as a really cool language to talk about who they were, how they related to each other, and what they were experiencing.

Then, when Trump got elected, I took my two favorite coworkers out to lunch and was like, “We gotta go [do something new] and I think there is room for something like Co-Star.” So we all left and started working on this thing the following summer - this is the summer of 2017 - and launched that October and have been growing at an insane rate since.

Did you always know that you wanted it to manifest as an app?

There was this moment [recently] when I was at the Apple store just looking at everybody waiting to get their phones fixed, and I noticed that everybody kind of looks like a broken cyborg when they don’t have their phones in their hands. It’s an app because apps are how we consume the world at this point.

What I think is really fascinating about this right now is that if you go out to a bar in Brooklyn, you’ll overhear a group of people downloading Co-Star on their phones and then starting to have this really amazing real-life conversation about what they’re reading. I think that play between online and offline is super fascinating and something we think about a lot internally. It’s very much idea behind how we built this thing.

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Why do you think people are so drawn to astrology right now? How have you been able to capture it in a way that millennials are drawn to?

When you sit down and listen to how people talk about astrology in the real world, it’s not really this hyper-predictive, “What lottery number should I play today?” which I think is the sort of vibe that a lot of the other astrology apps portray. Nobody is looking for which lottery number to play. They’re much more interested in using astrology to answer the question of how we can have a real conversation about ourselves and our reality.

Nobody is looking for which lottery number to play. They're much more interested in using astrology to answer the question of how we can have a real conversation about ourselves and our reality.

I think astrology has stuck around for thousands of years precisely because it is so good at being a kind of infrastructure for those conversations.

How do you think astrology has evolved, or has our understanding of it just evolved in our lifetime?

One of the coolest things about astrology is that some version of astrology, or the idea of talking about people based on where the stars are, has evolved in almost every single cultural context throughout the world.

If you are under the sky and looking at the stars, and the stars are out - it is very hard not to look at them. If you are with other people, similarly, it’s really hard not to look at them and start to see patterns. And what is cool about that is if you just compare, say, astrology in the way it’s practiced and thought about in India to the way it’s thought about in the American context, there are huge differences.

Then if you look at how it’s shifted in the last 10 or 15 years, Mars and Venus used to be super, super gendered concepts. It was like Mars is about masculinity and men and Venus is about femininity and women. Now that’s kind of gone, disappeared completely, over the past 10ish years.

Now Venus (for the most part) stands for love and tenderness and maybe feminine forms of energy, like social softness, self-care, etc., whereas Mars has shifted toward aggression, sex, taking action, which is cool because it’s less about hey the planets have genders, and it’s more interesting to isolate the behavior that they may be correlate to or parts of the personality.

What does a day in the life look like for you?

Really depends on the day – it’s been nuts lately. I’m in a lot of meetings. I try really hard to make time to do boring human stuff - like eat food and read a book, but that doesn’t always happen. So it often feels like a lot of running around.

How do you use astrology to inform your everyday life and decision-making?

It’s fascinating being in this position now. I’ve been using astrology for so long - to me, it’s this language for talking about humans. But I am now in this position where I have to make decisions based on a lot of other stuff; and one of my weird coping mechanisms, historically, (what I used to do) was I would ask everybody within the first conversation what their sun sign is and if they know what their moon and rising were.

Now I’m having to remove that tick from my conversational style. For instance, when interviewing a potential engineer, it’s actually not cool to ask that. But, in my personal life it’s just constant. “Oh that’s because you’re this moon,” or, “oh that’s because you’re this Venus, oh what’s their Mars?” Sometimes it’s more important than what their name is honestly.

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How would you say astrology affects our relationships? How can we use it to better understand the people in our lives?

If you look at the evolution of astrology over the past 100 years, sun sign-based astrology (editor’s note: The sign most often talked about in mainstream media is your sun sign) was invented in the ’20s or ’30s by this guy who was just selling newspapers and realized you can reduce everybody to a single sign that’s easy to identify based on date of birth. It’s not something that is 100% accurate - they solved that with cusps eventually - but, it worked really well to sell newspapers. Within maybe 20 years, 60 or 70% of British adults were reading their horoscopes at least monthly.

But one of the really terrible things about that in turn, everybody got reduced to this single archetype but that’s not how humans work, humans are incredibly complex, and internally contradictory, inconsistent, and change dynamically in all kinds of different ways. I think one of the things that is really valuable about full natal chart astrology is that it’s a language for complexity [of humans] at the end of the day.

Your moon sign, for instance, [is important because it] is really for when you are by yourself, drunk late at night, falling asleep; whereas your Venus sign is when you’re falling in love, whereas your Mercury is how you think and talk and how your brain operates. I think [the combination of these] is much closer to how human personality plays out.

I think the most powerful part of astrology comes once you can be like “you’re shutting down within this conversation because you are a Capricorn Mars.” You’re going to have a much more successful time doing that than if you were like “Why are you shutting down? It’s because you’re a monster.”

For someone who is not currently using the Co-Star app, what is the ideal way a user would engage with it in your mind?

Download the app, put in your date of birth, add your friends and you can look at your full chart, plus see your compatibility with friends when they add you back. You can also see updates based on where the stars are right now, you can send your friends messages and talk about it.


Are you seeing more people use astrology as a form of self-care and reflection? Do you have tips for using the Co-Star app for taking better care of yourself?

Absolutely. I think there is a wide open space and people are really searching for better ways to take care of themselves instead of scrolling through their phones waiting for that next like to pop up.

We noticed that a lot of people actually use the app late at night, which I find really really tender. It’s a way of thinking about what happened over the course of your day. It’s this framework for reflecting and saying, “How was my love life today? How was work really? What did I do that was right and what did I do that I can improve?”

It's a way of thinking about what happened over the course of your day. It's this framework for reflecting and saying, “How was my love life today? How was work really? What did I do that was right and what did I do that I can improve?”

What does self-care mean to you as an entrepreneur?

A friend of mine was joking the other night that my definition of self-care includes “I’m a robot that is required to eat food for my human body to continue functioning” – which is probably fairly accurate.

I’m not terribly romantic about self-care but that being said, I have a handful of long-term self-care strategies: I take a lot of time out to have short sweet conversation with friends, I throw a lot of dinner parties, and I’ve alternated between having themes for them or not. For a while the going theme was requiring people to have something to read aloud – preferably something that was their own authorship.

I like creating these ways to build intimacy between people who don’t know each other or have a basis for knowing each other. I also read a lot. My true guilty pleasure is a lot of trashy sci-fi – nothing to write home about.

How do you wind down after a long day?

Usually I’m on my couch, I turn off my phone, turn off my computer, and read and listen to music. Notifications rot your brain, I think. My true self-care strategy is not having almost any notifications turned on. It’s very hard to reach me immediately.

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What is your sign and what signs are you compatible with?

I am a Scorpio sun and a Cancer rising and a Leo moon. I am super compatible with Tauruses. Almost everyone I have ever dated seriously has been a Taurus. And I’m also super magnetized to Pisces. They’re super dreamy and sweet.

What is your most Scorpio quality?
I am hyper-obsessed with the idea of the truth and cutting away everything that is not the truth, for better or worse.

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Photos by Bridget Badore for GNI.