Do you need a SIM card for a GPS tracker, local logging versus real-time 4G tracking explained

GPS trackers vary significantly in how they work and whether they require a SIM card and mobile data connection. Local GPS logging stores position data on the device without transmitting it. Real-time 4G tracking uses a SIM to transmit location continuously to a server accessible from your phone. The right choice depends on whether you need live visibility or historical records. LockCar explains both approaches and offers both in its product range.

GPS trackers without a SIM card

GPS trackers that do not use a SIM card work by recording position data to internal memory and making it available for download when the device is accessed directly or via a local wireless connection. LockCar Duo RH and Duo RH local MCU systems record GPS route history to the device, accessible when the vehicle is connected to the LockCar system.

No-SIM GPS trackers provide historical route data but cannot send real-time location alerts. They are most appropriate for fleet route verification, mileage record-keeping, and situations where real-time visibility is not required. They have no ongoing data subscription cost.

4G GPS trackers with a SIM card

Real-time 4G GPS trackers use an embedded or inserted SIM card to transmit position data continuously to a cloud server. This enables the LockCar app to display the vehicle’s current position in real time, send immediate push notifications when geofences are crossed or unexpected movement is detected, and provide live camera access on dashcam-equipped systems.

4G GPS trackers require an active data SIM and associated data plan. LockCar One Plus and Duo RH Plus include 4G connectivity. Contact LockCar for current data plan options included with or available alongside each 4G system. The cost of real-time connectivity is justified by the significant security and operational benefits it provides compared to local-logging alternatives.

Relay immobiliser function, no SIM required

LockCar’s relay immobiliser function operates independently of any SIM card or mobile data connection. The physical relay break is controlled by the encrypted proximity tag signal, which uses a short-range 2.4GHz channel between the tag and the device. This function requires no internet connection, no SIM, and no ongoing subscription. The relay immobiliser works in any location regardless of cellular coverage.

This independence is an important security characteristic. Even if a criminal manages to block or jam the 4G connection, the relay immobiliser continues to prevent engine start. The physical relay break is not vulnerable to network disruption.

LockCar recommended products

Top recommendation

LockCar ONE, £199

Local GPS, no SIM required, relay immobiliser

Professional dashcam and relay immobiliser with local GPS recording. No SIM required for core function. For real-time tracking, step up to LockCar One Plus with 4G included.

LockCar One Plus, £259

4G SIM, real-time GPS, live alerts, immobiliser

Real-time 4G GPS with movement alerts, live camera, and relay immobiliser. The complete tracking and prevention package with SIM connectivity included.