How GPS Geofencing Works

Lil Tracker Location Guide

How GPS Geofencing Works

A geofence is a virtual safety zone drawn around a location such as a home, school, care residence or park. When the Lil Tracker device reports a location outside the active zone, the app can generate a geofence alert.

Geofencing is designed for larger safety zones. It is not an instant property-line alarm and should be used together with GPS location, calling and SOS features.

The centre point and radius define the safety zone

What Is a GPS Geofence?

A geofence is a circular area created on the map in the Lil Tracker app. You select the centre point, choose the size of the zone, give it a name and turn it on.

The geofence does not create a physical barrier and it does not continuously watch the exact boundary. The device must first obtain a location and send that location through its cellular data connection. The app then compares the reported location with the active zone.

1

Minimum Radius: 200 Metres

The smallest available setting is a 200 metre radius. The zone extends 200 metres in every direction from the centre point.

2

Maximum Radius: 2,000 Metres

Larger zones can be used for campuses, parks, neighbourhoods, care facilities and other broad areas.

3

Alerts Are Not Instant

An alert can only be generated after the device obtains and reports a new location outside the zone.

4

An Active SIM Is Required

The device needs cellular data, network coverage and enough battery power to report its location to the app.

Why the Smallest Zone Is 200 Metres

GPS locations naturally vary. Accuracy is usually strongest outdoors with a clear view of the sky and may be reduced indoors, near tall buildings, under heavy tree cover or when the device must rely on weaker location signals.

A very small geofence could create repeated false alerts even when the person wearing the device has not meaningfully left the property. The 200 metre minimum helps reduce unnecessary alerts caused by normal location variation.

A 200 metre radius is not a 200 metre-wide circle. The zone extends 200 metres from the centre in every direction, so the full circle is 400 metres across.
Place the centre point near the middle of the area you want to cover. Do not place the centre on the edge of the property. Increase the radius until the full home, school, residence or site is comfortably inside the circle.

How to Create a Geofence in the Lil Tracker App

  1. Open the Lil Tracker app and tap the map on the home screen.
  2. Tap the Geofence icon. It is normally the fourth icon from the top on the right side of the map.
  3. Tap the + button to create a new safety zone.
  4. Move the map so the centre marker is positioned near the middle of the location you want to cover.
  5. Enter a clear name such as Home, School or Care Residence.
  6. Use the slider to choose a radius from 200 to 2,000 metres.
  7. Slide the switch to the green On position and save the zone.
  8. Confirm that notifications are allowed for the Lil Tracker app in the phone settings of each caregiver who needs alerts.
After creating the zone, take the device outdoors and request its current location from the map. Confirm that the reported location appears inside the circle before relying on the geofence.

What Geofencing Is Best Used For

Good Uses

Larger zones around a home, school, care residence, park, campground, community centre or other broad location where leaving the general area is meaningful.

Poor Uses

A doorway, individual room, apartment unit, small backyard, exact property line or any situation requiring an immediate alert at the moment a boundary is crossed.

Geofencing should be treated as a secondary safety feature. For urgent situations, caregivers should also use the map, request a current location, call the device and use the available SOS and communication features.

How Quickly Will a Geofence Alert Arrive?

Geofence alerts are not generated the instant the wearer steps outside the circle. The device must obtain a new location, connect to the cellular network and report that location to the Lil Tracker platform.

A practical limitation: GPS, cellular networks and phone notifications are not perfect. An alert can occasionally be delayed or missed, so geofencing should support, not replace, direct human supervision when supervision is required.
Factor How It Affects the Alert
Location update interval When location is not being actively requested, the fastest regular update interval is approximately 10 minutes. The alert may not be generated until the next successful location update.
GPS conditions Outdoor GPS is generally more accurate. Indoor use, tall buildings, heavy tree cover and other obstructions can delay or reduce location accuracy.
Cellular coverage The device must have an active SIM, cellular data and network coverage to send the updated location.
Phone notifications The caregiver’s phone must allow notifications for the Lil Tracker app. Battery-saving or focus settings can delay or hide alerts.
Battery level A powered-off device or a device with a depleted battery cannot obtain or report a new location.
You can request the current location manually at any time. Open the map and use the location refresh control to ask the device for a new position. This is useful when you need to confirm where the wearer is now.

Geofence Troubleshooting

No Alert Received

Confirm that the zone is switched on, the SIM plan is active, the device is online and phone notifications are enabled.

Alert Arrived Late

This can occur when the device is waiting for its next location update or has weak GPS or cellular reception.

False Exit Alert

Move the centre closer to the middle of the property and increase the radius so normal GPS variation stays inside the zone.

Location Is Stale

Request the current location from the map. If the device remains offline, check the SIM, APN, battery and network coverage.

Only One Caregiver Sees Alerts

Check notification permission, focus mode and battery-saving settings on each caregiver’s phone.

Zone Will Not Save

Confirm that the zone has a name, the radius is within the allowed range and the switch is turned on before saving.

Frequently Asked Questions

Can I make the geofence smaller than 200 metres?
No. The minimum radius is 200 metres. Smaller zones would be more likely to create false alerts because GPS locations naturally vary.
Will I be alerted the exact moment the boundary is crossed?
No. The device must first obtain and report a new location outside the zone. The fastest regular location update interval is approximately 10 minutes when the location is not being actively requested.
Can I check the location before the next automatic update?
Yes. You can open the map and request the current location manually at any time, provided the device is powered on, online and able to obtain a location.
Why is the watch shown outside the zone when it is still at home?
Indoor or obstructed location signals can be less accurate. Request a current location outdoors, place the zone centre near the middle of the property and increase the radius if needed.
Does geofencing work without a SIM card?
No. The device needs an active compatible SIM with cellular data so it can send its location to the Lil Tracker app.
Does geofencing replace human supervision?
No. It is an additional layer of awareness and should not replace direct supervision when supervision is required.

Need More Help With Location Tracking?

Watch the geofence tutorial, compare Lil Tracker models or contact our support team for help setting up a safety zone.

Watch the Geofence Tutorial Compare Devices Contact Lil Tracker Support