What Co-Star is good at

Co-Star is the app that made astrology a group chat. Stark black-and-white design, NASA ephemeris data under the hood, a friend list that turns compatibility into a social feature, and push notifications with a tone so brutal they became a meme in their own right. In July 2026 it was reported that Co-Star had been acquired by the AI lab Midjourney, with the deal having closed the previous spring.

• ✓Unmistakable design, nothing else looks like it
• ✓The social layer: add friends, compare charts, argue about it
• ✓Short, sharp, quotable daily prompts
• ✓Free to use, with about 4.3 million monthly active users

Where Co-Star stops

Co-Star is designed to be read in four seconds and closed. That is a real skill, but it means nothing accumulates: no cards, no journal, no history you can look back through, and nothing that asks how last month went. It is also astrology only.

What Artemis does that Co-Star does not

Artemis is not a card-meaning lookup and not a horoscope feed. It is a tarot journal with a memory, and it works whether this is your first week or your tenth year.

You do not need to know the 78 cards to start. Artemis reads the spread for you in plain language, the full card library is a tap away when you want to look something up, and you can practise your own interpretations and have a person check them. Newcomers get a real reading on day one instead of a quiz.

Every reading is saved with your question, the cards, what you wrote, and the sky that day. Then Artemis reads back across all of it. It tells you the Tower has turned up four times since June. It notices that you only pull after midnight, and only when something is unresolved. It comes back six weeks later to ask whether the thing you were worried about actually settled down.

The part people do not expect is Your world. Mention your sister, your knee, the job you are waiting to hear about, and each one quietly gets its own page, built from your own writing without you filling in a single field. Open your sister months later and there is what you have actually said about her, alongside how today's sky sits against her chart and yours. That is the piece nothing else in this comparison has any version of.

Alongside that: your daily reading is keyed to the live sky rather than a generic sun-sign column, heavy readings end in a short somatic grounding practice so you close the app settled, you can practise interpreting spreads and get feedback, and you can receive interpretations written personally, by a person rather than generated.

Artemis vs Co-Star, feature by feature

Where we could not verify a feature from Co-Star's public materials, the row says so rather than guessing. Last reviewed September 2026.

So which should you use?

Pick Artemis if you want your readings to accumulate: a searchable journal of every spread, an app that notices the Tower has come up four times since June, a check-in six weeks later asking whether it calmed down, and the ability to photograph a spread from the deck you already own. That is the case for most people who read regularly.

Pick Co-Star instead if this is you: People who want astrology as a fast, funny, shared daily hit.

They are not mutually exclusive, and plenty of people run both. Artemis is where the practice lands once you are reading for real.

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