Cardio Flutter

A Flutter package to measure heart rate, blood pressure, SpO2, respiratory rate, and HRV using your device camera.

Features

Heart Rate — Real-time BPM with confidence level
Blood Pressure — Systolic and diastolic readings (mmHg)
Oxygen Saturation (SpO2) — Blood oxygen percentage
Respiratory Rate — Breaths per minute
Heart Rate Variability (HRV) — Stress and recovery indicator (ms)
Dual Authentication — API Key or Access Token modes
Cross-platform — Android and iOS

Installation

Add to your pubspec.yaml:

dependencies:
  cardio_flutter: ^1.0.3

Then run:

flutter pub get

Platform Setup

Android

Add the following permissions to android/app/src/main/AndroidManifest.xml:

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />

iOS

The package fully supports iOS 11.0+ via WKWebView.

Add the following keys to ios/Runner/Info.plist:

<key>NSCameraUsageDescription</key>
<string>Camera access is required for cardiovascular health measurement</string>
<key>NSMicrophoneUsageDescription</key>
<string>Microphone access is required for cardiovascular health measurement</string>
<key>io.flutter.embedded_views_preview</key>
<true/>

Usage

API Key Mode

import 'package:cardio_flutter/cardio_flutter.dart';

Navigator.push(
  context,
  MaterialPageRoute(
    builder: (context) => CardioWebView(
      apiKey: 'your-api-key',
      appUserId: 'user-123',
      organizationId: 'your-org-id', // optional in API key mode
    ),
  ),
);

Access Token Mode (Recommended for Production)

Navigator.push(
  context,
  MaterialPageRoute(
    builder: (context) => CardioWebView(
      accessToken: 'your-access-token',
      organizationId: 'your-org-id',
      appUserId: 'user-123',
      useAccessToken: true,
    ),
  ),
);

Parameters

Parameter	Type	Required	Description
`apiKey`	`String?`	For API key mode	Your Cardio API key
`accessToken`	`String?`	For token mode	Pre-fetched access token
`appUserId`	`String`	Yes	Your app's user identifier
`organizationId`	`String?`	For token mode	Organization ID
`useAccessToken`	`bool`	No	Use access token auth (default: `false`)
`validateApiKey`	`bool`	No	Validate API key on init (default: `true`)
`primaryColor`	`Color?`	No	Override UI theme color (default: `#317796`)

Result Model

The CardioResult model provides structured access to measurement data:

Field	Type	Description
`heartRate`	`int?`	Heart rate in BPM
`confidence`	`String?`	Measurement confidence level
`systolicBp`	`int?`	Systolic blood pressure (mmHg)
`diastolicBp`	`int?`	Diastolic blood pressure (mmHg)
`spo2`	`int?`	Blood oxygen saturation (%)
`respiratoryRate`	`int?`	Respiratory rate (breaths/min)
`hrv`	`int?`	Heart rate variability (ms)

Example

A complete example app is available in the example directory:

cd example
flutter run

License

See LICENSE file.