Castmates: AI Characters

Castmates is a private, on-device AI app for interactive character stories, running entirely on your iPhone. Most AI apps send every word you type to the cloud and make you sign in. Castmates doesn't: the model lives on your device, so your conversations are never sent to a server, there's no account, and it even works offline.

Meet a cast of 35 characters who actually stay in role. They don't reply like a chatbot: they narrate the scene, act, and remember what happened last time, so the story keeps building each time you come back.

A CAST FOR EVERY MOOD
Meet 35 hand-crafted characters across 8 genres:
• Friends & Mentors: a loyal best friend, a warm life coach, a hype-man trainer
• Romance: slow-burn crushes and devoted partners
• Fantasy: elven rangers, dark knights, fae sorceresses, gentle orcs
• Sci-Fi: sardonic ship AIs, starship captains, curious aliens
• Anime: tsundere rivals, shy schoolmates, bubbly childhood friends
• Historical: Regency nobles, samurai, Renaissance inventors, jazz-age icons
• Mystery & Horror: noir detectives, vampire countesses, eerie keepers
• Adventure: pirates, treasure hunters, wasteland survivors

DROP INTO A SCENE
Every character comes with ready-made scenarios, 127 in all, so you can jump straight into a story, or set your own opening scene and tone.

BUILD YOUR OWN
Create custom characters end to end: name, persona, greeting, appearance, tone, and a signature opening scene. Set their avatar from your photo library. They'll act exactly the way you wrote them.

PRIVATE BY DESIGN: ON-DEVICE AI
The whole AI runs locally on your iPhone. After a one-time model download:
• Your conversations are generated and stored on-device: never sent to a server
• No account, no sign-up, no profile
• Nothing is logged on our servers or used to train models
• It keeps working in airplane mode: on a flight, on the subway, off the grid

THEY REMEMBER YOU
Castmates summarizes past sessions, so characters recall who you are and pick up the thread days or weeks later.

FREE TO START
Start free with the full cast. Upgrade to Castmates Pro for unlimited messages and unlimited custom characters, and like everything else, they stay private on your device.

Castmates Pro options:
• Monthly subscription
• Annual subscription (best value)
• Lifetime purchase (one-time, not a subscription)

Payment is charged to your Apple ID at confirmation of purchase. Subscriptions automatically renew unless auto-renew is turned off at least 24 hours before the end of the current period; the Lifetime option is a one-time purchase that does not renew. Manage or cancel anytime in your App Store account settings.

Privacy Policy: https://get-castmates.com/privacy
Terms of Use (EULA): https://get-castmates.com/terms