Chapper

Chapper is a powerful, privacy-first AI chat client for iPhone and iPad that runs on-device models and connects directly to local LLMs, LM Studio, self-hosted AI servers, and OpenAI-compatible endpoints.

No accounts. No forced cloud. No subscription.

Whether you run LM Studio, Ollama, llama.cpp, or another OpenAI-compatible endpoint, Chapper gives you a polished, fully native iOS experience for chatting with your models, managing conversations, tuning inference settings, and working with local AI on your own terms.

Built in SwiftUI from the ground up, Chapper feels like a real iPhone and iPad app, not a web wrapper.

FEATURES

• On-Device Local Models MLX models and Apple Foundation Models directly on iPhone and iPad.

• Personas Custom AI personas with system prompt, tone, and language. Built-in: Code Expert, Translator, Teacher, Analyst, Brainstormer, and more.

• Thought Process Reasoning output from supported models in a collapsible panel.

• Rich Markdown Rendering Code blocks, tables, lists, emphasis, and structured responses.

• Model Management Browse, select, load, and unload models. View quantization, context length, tool and vision support.

• MCP Tools Web search, current time, server status, model listing, chat search, file access, URL fetching, and more.

• C.A.S.H. Terminal Sandboxed terminal for local workflows, file operations, shell scripting, and AI-assisted execution.

• Files App Integration Access Chapper workspace files in the iOS Files app.

• Memory Long-term information injected into conversations automatically.

• Prompt Templates Save and reuse common prompts instantly.

• Full Parameter Control Temperature, token limits, repeat penalty, Top-K, Top-P, Min-P, TFS-Z, Flash Attention, KV-cache offload, context length, structured output, and more.

• Search Full-text search across chats and message history.

• Export TXT, PDF, HTML, Markdown, JSON, CSV, and XML.

• Keychain Support API keys stored securely via iOS Keychain.

• iCloud Sync Optionally sync chats across devices.

• Analytics Dashboard On-device usage stats and activity insights.

• Server Tools Configure, save, and reuse server connections.

• JSON Lab Custom JSON requests and experimental API workflows.

• Chapper Pro One-time purchase. Unlocks unlimited chat history, all export formats, advanced sampling and structured output, MCP tools in normal chat, C.A.S.H. terminal, premium personas and templates, memory and analytics extras, iCloud sync, live vision chat, premium appearance options, and future Pro features. No subscription.

COMPATIBILITY

Works with on-device models, LM Studio, Ollama, llama.cpp, and OpenAI-compatible servers. Some features depend on your model or server.

PRIVACY

Chats stay on your device unless you enable iCloud sync or connect to your own server. No accounts. No third-party tracking.

Chapper is built for people who care about local AI, privacy, model control, and a true native iOS experience.