AI chat with no sign-up, on your iPhone

Updated

Castmates asks for no account. You install it, the model downloads once to your iPhone, and you're chatting with a character. There's no email, no password and no server holding your conversations. It has trade-offs, and they're listed below.

Free to start · No account · 100% on-device

How it works without a login

Most AI chat apps need an account because the AI runs on their servers, and the account is how they know who's talking. Castmates flips that. The model is on your phone, so there's nothing to log in to. Open the app, and the 35 characters are there.

  1. Install the app from the App Store. No sign-up screen.
  2. Let the model download once. It's about 2 GB, and you need a connection for this step only.
  3. Pick a character and start talking. Replies are generated on the phone.

What you need

If your iPhone has less memory, this app isn't a good fit, and we'd rather say so now than have you hit a slow, broken first chat.

What you give up

No account is the point, but it has costs you should know about before you install:

If you need your chats on every device, a cloud app with an account is the better choice. If you'd rather keep them on one phone and not on anyone's server, that's what this is built for.

Is "no sign-up" the same as private?

They're related but not the same. With no account, there's no profile to attach your chats to. Replies are generated on the phone and the chats stay there. The app does send anonymous usage stats, like which screens get used, but not your messages. Our private AI chat page covers that in more detail.

Cost

Free to start with 30 messages a day. Pro is $6.99 a month, $29.99 a year or $44.99 once, billed by Apple. Buying Pro doesn't need an account either, only your Apple ID.

Frequently asked questions

Can I chat with AI without making an account?
Yes. Castmates has no sign-up. You don't give an email, phone number or password, and you don't log in. Install the app, let the one-time model download finish, and start a conversation with one of the 35 characters.
What do I need for it to run?
An iPhone with 6 GB of RAM or more and about 2 GB of free storage for the model. Older iPhones with less memory can't run it well, so it isn't the right app for them. The download needs a connection once, and after that chatting works in airplane mode.
If there's no account, how do my chats survive a new phone?
They don't move for you. Chats are stored on the iPhone they were made on, and there's no account to restore them from. If you change phones or delete the app, the conversations go with it. That's the trade for keeping them off a server.
Is it as good as the big cloud chatbots?
Not at everything. The model is small enough to run on a phone, so it won't write code or answer trivia the way a large cloud model can. It's tuned for staying in character and telling a story, and that's where it does best.
Who is it for?
Adults (18+) who want to roleplay with characters and don't want to hand over an account or send their chats to a server. If you want a general assistant for work, a cloud app will do more for you.

Try Castmates free

35 characters, 127 scenarios, and every conversation stays on your iPhone.