An LLM co-pilot for Android chats that reads screens, not databases

What it does

Jev Chat Assistant is an Android app that uses the system accessibility service to read messages straight off your screen, runs them through an LLM pipeline for intent analysis and reply generation, then floats a translucent panel with three ranked candidate responses. You tap one to fill the input box; sending remains entirely manual. It supports WeChat, QQ, X (Twitter DMs), and Feishu via small per-app adapters, and keeps all keys and knowledge base data in local app storage.

The interesting bit

The project treats the accessibility tree as a generic message bus. Because WeChat obfuscates its node IDs for non-system services, the app disguises itself as SelectToSpeakService to read bubble text; when apps like Feishu draw text outside the tree entirely, it falls back to on-device ML Kit OCR on the bubble rectangles. Adding a new messenger means implementing one ChatAppAdapter to map the UI tree to a message list—everything downstream stays the same.

Key highlights

• Reads chat UI via accessibility nodes; falls back to on-device ML Kit OCR when apps draw their own text (Feishu)
• One core engine with pluggable ChatAppAdapters for each messenger; WeChat, QQ, X, and Feishu already implemented
• Structured analysis (“Jev”) evaluates intent, danger level (1–9), and recommended action in about a second before drafting replies
• Local knowledge base and contact profiles can be injected into prompts for context-aware suggestions
• Never auto-sends; only fills the input box via ACTION_SET_TEXT or clipboard paste

Caveats

• Chinese ROMs (Xiaomi/HyperOS) aggressively kill the background accessibility service even with battery exemptions, so the overlay may vanish until you interact again
• Feishu/Lark support currently depends entirely on OCR because text isn’t exposed to the accessibility tree; sender detection relies on read-status heuristics that can get “me” vs “other” backwards
• WeChat’s node obfuscation is bypassed by disguising the service class name, which could break on the next WeChat update

Verdict

Worth a look if you want an LLM wingman for Android messaging without rooting or patching apps. Skip it if you need desktop support, rely heavily on Feishu, or run a ROM that murders background accessibility services.