Dimension scores are derived from public data and fields; weighted into the composite. Reference only.
Chapper is an iPhone and iPad LLM client from Prevolut. It is positioned not as a simple chat wrapper, but as a “console-style” mobile tool that can connect to local or remote AI backends. It is optimized for LM Studio, while also supporting Ollama, llama.cpp, and any OpenAI-compatible endpoint, with connections available over a local network or HTTPS.
Its main strength lies in model and workflow control: real-time streaming output, collapsible reasoning/thinking traces, Markdown and code highlighting, structured output via JSON Schema, vision and file uploads, web URL context injection, long-term memory, and TTS. For advanced users, it also offers controls for model downloading and loading, context length, sampling parameters, Flash Attention, GPU KV-cache offload, and more. MCP tools, C.A.S.H. Shell workflows, and JSON Lab make it feel closer to a developer debugging and automation workbench.
The app is free to download and requires no account; the free version is limited to 20 sessions. Pro is a one-time purchase, with no subscription or hidden fees. It unlocks unlimited history, advanced sampling, all export formats, Persona, templates, MCP, long-term memory, analytics dashboard, iCloud sync, and future features, though the website does not disclose the exact price. On privacy, the main text clearly states that conversations are stored locally, Prevolut does not collect data, API keys are securely stored inside the app, and iCloud sync is optional and end-to-end encrypted.
Its advantages are an open backend approach, privacy-friendly design, a complete native mobile experience, and support for both everyday chat and developer debugging. The limitations are also clear: it does not provide cloud-hosted large models itself, output quality depends on the external model, it only supports iPhone/iPad, and Chinese UI support is not explicitly confirmed—only that 13 interface languages are available. It is best suited to AI enthusiasts, developers, researchers, and privacy-conscious users who already have local models or API services.
The main text does not state whether the website or App Store listing is accessible from mainland China, so this remains unknown. Actual usage also depends on the model service being connected: local LM Studio/Ollama setups are generally more controllable, while connecting to overseas OpenAI-compatible services may involve network and payment restrictions. Alternatives to compare include Chatbox, Open WebUI, LM Studio, and Msty.
⚠ This review is compiled from public sources and does not constitute a purchase recommendation. Verify all facts on the vendor's official site. Verify on chapper.app official site.
chapper.app is an Netherlands AI Apps provider. TG4G tracks its product information, an overall rating of 7.0/10, and a China-accessibility score of Workable. Click "Visit Official Site" to reach chapper.app directly.