GTS — Parent Trip Tracking Prototype

A polished Flutter prototype of the GTS (Go To Shore) parent experience: a parent opens the app while their child is travelling home from school, sees the live journey at a glance, receives plain-language safety alerts, and can raise an SOS with an explicit confirmation step.

_{One continuous run: live tracking → overspeed alert → recovery → lost location → arrival → SOS confirm → success.}

Screens

Live trip	Overspeed	Location lost	SOS confirm	SOS raised
ETA hero, speed, distance, progress	Red alert, exact speed vs. limit	Amber alert, "NO SIGNAL" chip	Deliberate confirmation step	Persistent success state

Features

• Active trip screen — child, driver (name, rating, trip count), vehicle + plate, school → home, live status pill that a safety alert can take over
• Real map — OpenStreetMap via flutter_map: travelled route (solid) vs. remaining (dashed), school/home markers, an animated driver marker that glides between updates with an alert-colored pulsing ring, recenter control
• Live metrics — ETA (hero number + wall-clock estimate), current speed, distance to destination, school→home progress bar, all recomputed every tick
• Safety alerts (plain parent language, no technical jargon)
  • Overspeeding — red: "Driver is travelling faster than the safe limit." with current speed vs. limit
  • Location stopped/unavailable — amber: "We haven't received a location update for a while." with time since last update
  • Both show a brief green resolved state when the condition clears
• SOS flow — tap → confirmation sheet → raising → success, then a persistent "SOS raised · Safety team notified" bar for the rest of the trip
• Loading / error / retry states for the initial trip fetch
• Demo controls (tune icon, top-right) — pause/resume, trigger overspeed, trigger lost location, jump near arrival, restart

Run

flutter pub get
git clone https://github.com/Shoaib20786/gts_parent_tracking.git
cd gts_parent_tracking
flutter pub get
flutter run

Internet access is needed for OpenStreetMap tiles; everything else is local. Built and verified with Flutter 3.35.5 / Dart 3.9.2 on Android.

flutter test                     # provider + route geometry unit tests
flutter build apk --release      # build/app/outputs/flutter-apk/app-release.apk

Architecture

lib/
  app/                    MaterialApp + theme tokens (AppColors, AppTextStyles)
  core/
    constants/            safety thresholds & simulation tuning in one place
    models/               Trip, DriverLocation, SafetyAlert
  features/active_trip/
    data/                 mock route (LatLng polyline) + deterministic timeline
                          + RouteGeometry (progress → position, path splitting)
    provider/             ActiveTripProvider — all state & simulation logic
    presentation/         screen + presentational widgets (map, metrics,
                          header, driver card, alert card, SOS button/sheet)
test/                     provider & geometry unit tests (no timers needed)

The key design decision: every displayed value (position, speed, distance, ETA, status, alerts) is derived purely from an index into a deterministic mock timeline, advanced by a periodic Timer. The demo controls and the unit tests drive the exact same seek path as the timer — so the demo plays out identically on every run and the logic is testable without any timer machinery.

The location-lost alert is not scripted directly: the provider detects that the position hasn't changed for N consecutive ticks — the same rule a real backend would apply.

All driver movement is simulated with deterministic local mock data — no backend, authentication, or real GPS is required. The SOS flow is fully simulated; no real emergency service is contacted.

What was hard

Making the demo deterministic without making it fake. Every value on screen (position, speed, ETA, alerts) is derived from an index into a mock timeline that a Timer advances, so the demo controls and the unit tests drive exactly the same seek path. The "location lost" alert is not scripted: the provider detects N unchanged ticks, the same rule a real backend would apply. The driver marker also had to glide between updates without fighting flutter_map rebuilds.

Status

Prototype, complete · Last updated August 2026

Licence

MIT