Vitrus for Flutter & Dart

Cookie-free, privacy-first analytics for Flutter and Dart apps — the native SDK for Vitrus, the open-source analytics where every number opens the query that counted it.

• Your users' ids never leave the device: identify sends a SHA-256, hashed again on the server.
• No advertising id, no persistent device id, no tracking.
• Offline queue with batching, and honest timestamps for events sent later.
• Your app shows up next to your website in the same workspace: Portfolio, Users, Lifecycle.
• Two dependencies, both from the Dart team: crypto and http.

Install

flutter pub add vitrus      # or: dart pub add vitrus

or in pubspec.yaml:

dependencies:
  vitrus: ^0.1.1

Flutter setup

Keep the daily value and the offline queue between launches, and flush when the app goes to the background:

import 'package:flutter/widgets.dart';
import 'package:path_provider/path_provider.dart';
import 'package:vitrus/vitrus.dart';

Future<void> main() async {
  WidgetsFlutterBinding.ensureInitialized();
  final dir = await getApplicationSupportDirectory();
  await Vitrus.instance.configure(
    site: 'SITE_ID',                 // dashboard → Install
    storage: FileStorage(dir.path),
    appVersion: '2.3.0',             // or from package_info_plus
    appName: 'Tallyhook',
  );
  WidgetsBinding.instance.addObserver(_VitrusLifecycle());
  runApp(const MyApp());
}

class _VitrusLifecycle with WidgetsBindingObserver {
  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.paused) Vitrus.instance.flush();
    if (state == AppLifecycleState.resumed) Vitrus.instance.appOpen();
  }
}

Tablets: pass isTablet: MediaQuery.sizeOf(context).shortestSide >= 600 to configure if you want them counted apart from phones — Dart alone cannot tell them apart. Self-hosted: host: Uri.parse('https://analytics.example.com').

Use

final v = Vitrus.instance;

v.screen('Invoices');                       // a screen view: /screen/Invoices
v.track('invoice_sent', {'items': 3});      // what people do
v.identify(user.id);                        // on every launch while signed in
v.identify(null);                           // on sign-out
v.plan('pro');                              // free · pro · cancelled — your labels
v.revenue(4.99, 'USD');                     // dollars, not cents

For screen views from navigation, call screen in a NavigatorObserver.didPush.

What is sent

Sent	Not sent
Screen and event names, their properties (personal fields removed)	Your user's raw id, email, name or phone
sha256(site + "|" + userId) when you call identify	Advertising id, Android id, any persistent device id
App version, OS, phone / tablet	Location, contacts, anything from other apps
A random value regenerated every UTC day (counts visitors without following anyone)	Timestamps from the device clock within a launch

Properties whose key names personal data (email, phone, first_name, address, password, token, ip, …) and values shaped like an email address or an international phone number are dropped on the device — and again on the server.

How times work. The server's clock is the clock. An event sent later carries how long ago it happened, from a monotonic stopwatch; only events queued in an earlier launch fall back to the wall clock. Events older than a day are dropped.

Sending. Batches of up to 50 to /api/batch: when 50 are waiting, every 15 seconds, and on flush(). Offline, 429 or 5xx: kept and retried. Any other 4xx: dropped — retrying would not change it.

Store forms

Google Play — Data safety: App activity → App interactions (collected, not shared, not processed ephemerally, purpose: Analytics). If you call identify: Personal info → User IDs (collected, not shared, purpose: Analytics). Data is encrypted in transit; Vitrus does not share it with third parties.

App Store — privacy: Product Interaction (not linked) and, if you call identify, User ID (linked) — both for Analytics, not used for tracking. No App Tracking Transparency prompt is needed: nothing here is tracking in Apple's sense.

License

Apache-2.0. The server and dashboard: Vitrus-Dev/vitrus.