This article explains how EarthRanger Mobile (Android and iOS) captures and displays tracking points, why certain gaps or missing segments may appear, and what device settings may cause interruptions. Use this guide to help diagnose and resolve common tracking issues reported by field users. 

1. Ensure Proper Device Settings (Android Only)

Android devices apply aggressive background and battery optimizations that can prevent EarthRanger from collecting or sending tracking updates. Confirm the following settings before troubleshooting further.
 

Required Android Settings:

Enable Location Services
Open Settings > Location Ensure Location is turned ON
Set mode to High Accuracy Go to Settings > Location > Mode or Location Accuracy Select High accuracy (uses GPS + Wi-Fi + Bluetooth + mobile networks) Restart your device
EarthRanger App Permissions Verify these permissions:
Location: Allow all the time
Physical activity: Allowed

2. Android OS–Specific Requirements

Android 14

Samsung includes built-in “Guardian” modules that may kill background apps.

• Battery Guardian
  • Disable App power saving (may close EarthRanger if it uses “too much battery”).
• Keep Open
  • Open the Recent Apps screen.
  • Long-press or select EarthRanger and choose Keep Open to prevent Android from closing it.

Android 13

• Battery:
  • Go to Settings > Apps > EarthRanger > Battery > Unrestricted
• Permissions Reset:
  • Disable Remove permissions if app is unused
• Auto Optimization:
  • Disable Settings > Battery and Device Care > Auto Optimization > Restart when needed

Android 11

Android 11 restricts background activity unless excluded from optimizations.

Battery Optimizations

• Go to Settings > Apps > EarthRanger > Battery > Battery optimization
• Choose All apps
• Select EarthRanger > Don’t optimize

Background Usage Limits

• Open Settings > Battery > Background usage limits
• Disable Put unused apps to sleep

Other features such as Adaptive Battery or Adaptive Power Saving should also be turned off if they affect tracking.

3. Understand App Behavior When Closed

Android Behavior

When the EarthRanger app is fully closed/swiped away:

• Tracking continues in the background, and points are sent to the platform.
• The Android app does NOT redraw points collected while closed.

This means:

• The mobile app map may show a gap in the route.
• The web platform map will show the complete track, including points recorded while the app was closed.

App was closed App was reopened When the app is fully closed, Android does not redraw tracking points captured while the app was closed.   But all tracks were uploaded successfully to the web.

iOS Behavior

When the EarthRanger app is fully closed/swiped away:

• iOS does redraw all points collected while the app was closed (if background permissions are granted).

This means:

• The mobile app map should not show a gap in the route when the app was closed and tracking.
• The web platform map will show the complete track as well

4. Tracking After Being Stationary (iOS 25 m Movement Rule)

Both Android and iOS optimize battery usage by reducing GPS activity when the device is not moving. iOS applies an additional rule to resume tracking.

iOS Behavior

If the device has been immobile for a period, iOS may pause background updates.

• To reactivate tracking, iOS requires movement greater than 25 meters.

Only after the device moves this distance will new tracking points be recorded and sent.

This may result in an initial gap when movement resumes.

User stops at a location for several minutes. iOS pauses GPS updates. User begins moving again. 2. Only after the device has traveled ~25 meters, tracking resumes. The resulting track shows a short missing segment from the moment the movement started until the threshold was met.

Android Behavior

• Android typically resumes tracking more smoothly after immobility.

It does not require a strict distance threshold like iOS.

5. High-Speed Movement Filtering (Platform Behavior)

The web platform applies a speed validation check, so if you are traveling on a high speed you may not see these tracking points recorded. This is editable in the site admin. The default value for subject speed is 200KM/H; this can be increased for individual subjects. 

Behavior

• If a GPS point implies a high speed above the platform threshold, the platform rejects that point.
• The point is not stored and is not displayed on any map.

User Impact

• Tracks may show straight lines, gaps, or missing segments after high-speed travel.

6. Why Points May Still Be Missing: GPS Signal Errors Not Caused by EarthRanger

Even when all app settings and permissions are correct, you may still see missing points, gaps, or sudden jumps in a track. In many cases, this happens because the device is receiving poor or distorted GPS signals, not because of an EarthRanger issue.

What Is GPS/GNSS?

Most mobile devices use GPS (Global Positioning System) or GNSS (Global Navigation Satellite System) to determine location.
These systems rely on clear, uninterrupted signals from multiple satellites.

If the signal reaching the device is weak or distorted, the location recorded will be inaccurate and EarthRanger will intentionally filter out bad data to avoid zigzags, jumps, or false tracks.

Common Causes of GPS Signal Errors

These conditions can interfere with the satellite signal before it reaches the device:

• Obstructions
  Tall buildings, dense forests, mountains, caves, and heavy canopy can block or weaken the signal.
• Signal reflection (Multipath interference)
  Satellite signals bounce off surfaces such as buildings, metal roofs, vehicles, or rocks, causing delayed or inaccurate readings.
• Atmospheric conditions
  Weather systems or ionospheric disturbances can temporarily degrade accuracy.
• Satellite alignment or availability
  If too few satellites are above the horizon, or their geometry is weak, the device cannot produce a precise location.
• Device hardware limits
  Some phones and tablets have lower-grade GNSS receivers that naturally generate more inaccurate positions.

What You Might See in EarthRanger

When GPS signal quality is poor, the device may produce:

• Sudden jumps or “teleporting” points
• Zigzag lines while moving slowly
• Missing segments in the track
• Straight lines connecting gaps when bad points were filtered out
• False movement when standing still
• Tracking that looks erratic in dense cities or forests

How These Errors Affect the App’s Behavior

To ensure cleaner tracking and avoid misleading routes, the app uses accuracy thresholds. If a GPS point has a high reported inaccuracy (e.g., ±25 meters), the app may:

• Reject the point entirely
• Avoid drawing it on the map

This means:

EarthRanger filters poor-quality or unrealistic points to protect map accuracy, which means some points will intentionally not be drawn if the signal was unreliable.

Key Takeaway

EarthRanger Mobile relies on the quality of the GNSS data provided by the device. Even with optimal device settings, GPS signal quality can vary depending on the environment and hardware. When poor signals occur, the device may send inaccurate points that EarthRanger correctly filters out. These environmental and hardware-based inaccuracies affect all GPS/GNSS-enabled applications, not just EarthRanger.

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