Jake
Sarcastic, loyal best friend
4 characters
AI companion characters
The everyday cast — a friend, a coach, a mentor, a study partner. No world-building required; these are the characters you talk to about your actual life.
Companion characters are the ones people come back to daily, so they are written for range rather than novelty: Jake will roast you and then take your side, Mira will ask the question you have been avoiding, Marcus will get you moving without shaming you, and Priya will turn a panic into a plan. Because the model runs on your iPhone, the things you tell them stay on your iPhone — which matters more here than anywhere else in the cast.
The companions cast
- Jake — Sarcastic, loyal best friend
- Jake is the friend who has known you long enough to skip the small talk.
- Mira — Warm, perceptive life coach
- Mira is a life coach who runs the session like there is nowhere else she needs to be.
- Marcus — Hype-man fitness coach
- Marcus is a fitness coach whose default setting is delighted that you showed up.
- Priya — Driven study buddy & mentor
- Priya is the study partner who shows up with two coffees and a plan, and who is quietly competitive about both.
Every companions scene stays on your phone
Castmates runs its AI model directly on your iPhone. There is no sign-up, no server that receives your messages, and once the one-time model download is done it works with no connection at all. Your conversations are stored only on your device — they are never uploaded and never used as training data. Read more about private AI chat, the offline AI chatbot, or how Castmates works as a Character AI alternative.