Co-Star
In short: Co-Star is a social astrology app that creates birth charts and daily horoscopes and lets users add friends to compare compatibility. Founded in 2017 in New York by Banu Guler, Anna Kopp and Ben Weitzman, it was bought by AI company Midjourney, as reported in July 2026. It matters to dating because astrology compatibility is the model that niche matchmaking apps are often compared with.
Key facts
| Type | Dating app |
|---|---|
| Headquarters | New York, United States |
| Founded | 2017 |
| Status | Active; acquired by Midjourney (deal closed spring 2026, reported July 2026) |
| Website | costarastrology.com |
| LinkedIn profile | |
| Developer / legal entity | Co-Star Astrology Society [Co-Star Personalized Astrology - App Store, 2026] |
| Core features | Birth charts, personalised daily horoscopes and friend compatibility comparison; free with in-app purchases [Co-Star Personalized Astrology - App Store, 2026] |
| Content method | Uses NASA data, interpreted by human astrologers working with AI, per the Google Play listing [Co-Star Personalized Astrology - Google Play, 2026] |
| Headquarters | 401 Broadway, Suite 610, New York, NY 10013, United States (developer address on Google Play) [Co-Star Personalized Astrology - Google Play, 2026] |
| Founders and founding year | Founded in 2017 by Banu Guler, Anna Kopp and Ben Weitzman [Co-Star - Wikipedia, 2017] |
| Funding | $750,000 pre-seed (2018), $5.2 million seed (2019), $15 million Series A led by Spark Capital (April 2021) [Co-Star - Wikipedia, April 2021] |
| Ownership | Acquired by Midjourney; deal closed in spring 2026 and was reported by Bloomberg in July 2026; financial terms not disclosed [AI Startup Midjourney Buys Astrology App Co-Star - Bloomberg, 24 July 2026] |
| Users | About 4.3 million monthly active users, per Sensor Tower data cited by Bloomberg [AI Startup Midjourney Buys Astrology App Co-Star - Bloomberg, 24 July 2026] |
| Leadership after acquisition | Founder Banu Guler remains in charge of Co-Star, with Midjourney CEO David Holz saying it stays under her control and direction; her team of about two dozen joins Midjourney [Midjourney Buys Co-Star To Build Its First Consumer AI Apps , July 2026] |
| Official website | costarastrology.com [Co-Star - LinkedIn, 2026] |
About Co-Star
Co-Star is a mobile astrology and social networking app. Users enter their birth date, time and place to get a natal chart and daily horoscopes, and they can add friends to compare charts and see a compatibility reading. Its App Store and Google Play listings describe the content as built from NASA data and interpreted by human astrologers working with AI. The app is free to download and sells optional in-app purchases such as advanced relationship charts. The developer is listed as Co-Star Astrology Society, with an address at 401 Broadway in New York.
The company was founded in 2017 by Banu Guler, Anna Kopp and Ben Weitzman. Wikipedia reports a $750,000 pre-seed round in 2018, a $5.2 million seed round in 2019 and a $15 million Series A led by Spark Capital in April 2021, when it reported more than 20 million downloads. An in-app AI feature called The Void was added in 2023.
In July 2026 Bloomberg reported that Midjourney had bought Co-Star, saying the deal closed in the spring and that terms were not disclosed. Bloomberg cited Sensor Tower data of about 4.3 million monthly active users. Reports say Guler continues to lead the app and that about two dozen staff joined Midjourney.
For the dating industry, Co-Star is not a dating app. It is an astrology product with a friend and compatibility layer, and DII has cited it as a precedent for astrology-led matchmaking and niche apps.
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Questions about Co-Star
What is Co-Star?
Co-Star is a social astrology app that generates birth charts and daily horoscopes and lets users add friends to compare compatibility.
Who owns Co-Star?
Midjourney bought Co-Star. Bloomberg reported in July 2026 that the deal closed in the spring, and financial terms were not disclosed.
Who founded Co-Star and where is it based?
Banu Guler, Anna Kopp and Ben Weitzman founded it in 2017. It is based in New York.
Is Co-Star a dating app?
No. It is an astrology app with a friend and compatibility feature. It is relevant to dating because astrology compatibility is a common reference for niche matchmaking products.
Where is Co-Star based?
Co-Star is based in New York, United States.
When was Co-Star founded?
Co-Star was founded in 2017.
Also known as: Co-Star Astrology Society, Co-Star Personalized Astrology.