Learn how to build a live map that follows user movement in real time using only JavaScript and the browser’s built-in Geolocation API.

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Introduction

You’ve seen it before, apps like Google Maps, Uber, and Strava that track your location and show it updating live.

But here’s something most developers don’t realize:
You can build your own real-time tracking map using nothing more than the Geolocation API and a few lines of JavaScript.

No frameworks.
No server setup.
No external SDKs required.

In this post, you’ll learn how to:

• Access the user’s live location in the browser.
• Display it on a real map.
• Automatically update the position as the user moves.s
• Handle permissions, errors, and best practices

Let’s bring real-time maps to your next web project.

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1. What Is the Geolocation API?

The Geolocation API is a native browser feature that lets your web app access the device’s physical location, usually through GPS, Wi-Fi, or mobile networks.

It provides two main methods:

navigator.geolocation.getCurrentPosition(success, error, options);
navigator.geolocation.watchPosition(success, error, options);

• getCurrentPosition() Gives you the user’s current coordinates once.
• watchPosition() Continuously tracks updates in real time.

And yes, it works on mobile browsers too (with permission).

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2. Get the User’s Location Once

Let’s start simple: a one-time location request.

<button id="getLocation">Get My Location</button>
<p id="output"></p>

<script>
  const output = document.getElementById('output');
  document.getElementById('getLocation').addEventListener('click', () => {
    if (!navigator.geolocation) {
      output.textContent = 'Geolocation is not supported by your browser.';
      return;
    }
    navigator.geolocation.getCurrentPosition(
      (position) => {
        const { latitude, longitude } = position.coords;
        output.textContent = `Latitude: ${latitude}, Longitude: ${longitude}`;
      },
      (error) => {
        output.textContent = `Error: ${error.message}`;
      }
    );
  });
</script>

✅ Once the user grants permission, you’ll see their coordinates appear.
 Now, let’s make it move in real time.

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3. Track Location Live with watchPosition()

watchPosition() keeps listening for changes and updates as the device moves.

<p id="status">Tracking your location...</p>

<script>
  const status = document.getElementById('status');
  if (navigator.geolocation) {
    const watchId = navigator.geolocation.watchPosition(
      (pos) => {
        const { latitude, longitude, accuracy } = pos.coords;
        status.textContent = `
          Latitude: ${latitude.toFixed(5)}, 
          Longitude: ${longitude.toFixed(5)}, 
          Accuracy: ±${accuracy}m
        `;
      },
      (err) => {
        status.textContent = 'Error: ' + err.message;
      },
      { enableHighAccuracy: true, maximumAge: 0 }
    );
    // stop tracking after 5 minutes
    setTimeout(() => navigator.geolocation.clearWatch(watchId), 300000);
  } else {
    status.textContent = 'Geolocation not supported.';
  }
</script>

Now you’ve got live updates every few seconds, perfect for tracking movement or navigation.

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4. Display the User’s Location on a Map

Let’s make things visual.
 You can use Google Maps or the open-source Leaflet.js library.
 We’ll use Leaflet since it doesn’t need an API key.

Step 1: Add Leaflet

<link
  rel="stylesheet"
  href="https://unpkg.com/leaflet@1.9.4/dist/leaflet.css"
/>
<script src="https://unpkg.com/leaflet@1.9.4/dist/leaflet.js"></script>

Step 2: Create a Map Container

<div id="map" style="height: 400px;"></div>

Step 3: Initialize the Map and Marker

<script>
  const map = L.map('map').setView([0, 0], 13);
  L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
    attribution: '© OpenStreetMap contributors',
  }).addTo(map);

  const marker = L.marker([0, 0]).addTo(map);
</script>

Now you have a basic map loaded with OpenStreetMap tiles.

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5. Combine It All: Real-Time Tracking on the Map

Here’s the complete code:

<link
  rel="stylesheet"
  href="https://unpkg.com/leaflet@1.9.4/dist/leaflet.css"
/>
<script src="https://unpkg.com/leaflet@1.9.4/dist/leaflet.js"></script>

<div id="map" style="height: 400px;"></div>
<script>
  const map = L.map('map').setView([0, 0], 15);
  L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
    attribution: '© OpenStreetMap contributors',
  }).addTo(map);
  const marker = L.marker([0, 0]).addTo(map);
  if (navigator.geolocation) {
    navigator.geolocation.watchPosition(
      (pos) => {
        const { latitude, longitude } = pos.coords;
        const coords = [latitude, longitude];
        marker.setLatLng(coords);
        map.setView(coords, map.getZoom());
      },
      (err) => console.error(err),
      { enableHighAccuracy: true, maximumAge: 0 }
    );
  } else {
    alert('Geolocation not supported on this device.');
  }
</script>

✅ This version tracks your position live and moves the map marker as you move, all using native browser APIs.

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6. Optional: Draw the Path (Route Tracking)

If you want to show movement history (like a running route), store previous coordinates and draw a polyline.

const path = [];
const line = L.polyline(path, { color: 'blue' }).addTo(map);

navigator.geolocation.watchPosition((pos) => {
  const { latitude, longitude } = pos.coords;
  const coords = [latitude, longitude];
  path.push(coords);
  line.setLatLngs(path);
  map.setView(coords);
});

Now you can literally see your route as it’s being drawn live.

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7. Handle Permissions and Errors Gracefully

Always handle permissions responsibly:

navigator.geolocation.getCurrentPosition(success, (error) => {
  switch (error.code) {
    case error.PERMISSION_DENIED:
      alert('You denied location access.');
      break;
    case error.POSITION_UNAVAILABLE:
      alert('Location unavailable.');
      break;
    case error.TIMEOUT:
      alert('Request timed out.');
      break;
    default:
      alert('Unknown error.');
  }
});

Always explain to users why you need their location before prompting. Transparency builds trust.

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8. Security and Privacy Tips

• The Geolocation API only works over HTTPS (except localhost).
• Only request location after user interaction (e.g., button click).
• Never store or share location without consent.
• Stop tracking when it’s no longer needed (clearWatch).

Privacy isn’t optional; it’s part of good engineering.

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9. Real-World Use Cases

Here’s where Geolocation-based real-time maps shine:

These features are easy to implement but instantly raise your app’s value.

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10. Browser Support

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Conclusion

The Geolocation API gives you everything you need to make your web app aware of the real world.

With just a few lines of JavaScript, you can build live maps, real-time trackers, and route visualizations all powered by the browser itself.

No plugins. No backend. Just the open web.

Pro Tip: Combine the Geolocation API with WebSockets or Firebase for multi-user live tracking (e.g., tracking friends or fleets on one shared map).

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Call to Action

Would you use real-time location in your next web app?
Share your ideas in the comments and bookmark this post for your next JavaScript project.