Fluistern

Voice-to-text overlay for Android. Press and hold the floating mic icon to record speech, release to transcribe via Groq Whisper API, and paste the result into any text field.

How it works

1. Tap any text field — the Fluistern mic icon appears automatically next to the keyboard
2. Hold the icon — it expands into a recording bar with a live waveform
3. Release — your speech is transcribed and pasted into the text field

The overlay hides automatically when no text field is focused.

Features

• Floating overlay that auto-shows/hides via Android Accessibility Service
• Press-and-hold to record, release to transcribe (no extra buttons)
• Groq Whisper API integration (whisper-large-v3)
• AAC/M4A compressed audio (~10-15KB per 5s) for fast upload
• Clipboard-based text insertion (works with all apps)
• Draggable icon with persisted position
• Language selection (auto-detect or 13 specific languages)
• Dark theme UI with settings for API key and language

Setup

1. Get a free API key from console.groq.com
2. Install the app and paste your API key in Settings
3. Grant permissions: Microphone, Display Over Apps, Accessibility Service
4. Open any app, tap a text field, and use the floating icon

Install

Download the latest APK from Releases and install it on your device.

Build from source

flutter pub get
flutter build apk --release

Install:

adb install -r build/app/outputs/flutter-apk/app-release.apk

Architecture

lib/
  main.dart                  — App entry, dark theme
  screens/
    home_screen.dart         — Setup checklist, status card, how-it-works
    settings_screen.dart     — API key input, language dropdown
  services/
    platform_service.dart    — Platform channel bridge to native Android
    groq_api_service.dart    — Dart-side Groq API (backup)

android/.../kotlin/com/fluistern/fluistern/
  MainActivity.kt                    — Platform channel handler
  FloatingService.kt                 — Overlay service: recording, transcription, custom view
  FluisternAccessibilityService.kt   — Auto-show/hide overlay, clipboard text insertion

assets/
  ic_logo.svg              — App icon (single source of truth)
  ic_logo_foreground.svg   — Adaptive icon foreground layer

Tech

• Flutter for the settings UI
• Native Kotlin for the overlay service (custom View with Canvas drawing)
• MediaRecorder with AAC encoding for compressed audio
• Groq Whisper API for transcription (multipart upload)
• AccessibilityService for detecting text field focus and inserting text via ACTION_PASTE
• WindowManager overlay with TYPE_APPLICATION_OVERLAY