Co-Star is an astrology app known for its sharp writing style and social chart comparison. It uses NASA data, supports friend chart comparison and compatibility, sends personalized daily horoscope notifications, teaches users how to read a birth chart, and offers premium question, natal-chart, love-report and relationship features.
What Stands Out
- The tone is pointed and memorable, which has become part of Co-Star's identity.
- Friend comparison and compatibility create a social astrology loop.
- Birth chart learning and full-chart framing make it broader than sun-sign horoscopes.
Product Notes
Co-Star is most interesting when users care about astrology as social language. It is not the deepest technical astrology tool, but it is strong at turning chart data into daily prompts and relationship conversations.

