Using an external GPS receiver

How to set it up

1. Charge the receiver and mount its antenna with a clear view of the sky (the cab roof beats the dashboard).
2. Pair it in iOS Settings → Bluetooth, the same way you'd pair headphones. Some receivers use their own companion app for setup; follow the maker's instructions.
3. Open Tractor GPS – Field Guidance and drive. Fields, guidance and the work log use the receiver's position automatically.
4. Wi-Fi-only iPad: also switch on Settings → External GPS Receiver in the app, so it knows a position source is connected and stops showing the "no built-in GPS" message.

Which receivers work

Receivers that supply their position to iOS location services, which in practice means Apple MFi-certified GPS receivers. We don't test or certify individual models, and the app can't talk to a receiver directly, so a receiver that only works inside its maker's own app won't help here.

What accuracy to expect

It depends entirely on the receiver, so use the manufacturer's figure. Two common consumer receivers, for scale (read 20 October 2026):

Those figures are metres, not feet, and a dual-frequency iPhone with a clear sky view is typically within 0.5–0.7 m side-to-side, so on a newer iPhone a basic consumer receiver may add little. A consumer receiver can be steadier than a phone's own GPS, but it's not decimetre or centimetre guidance. For that you need an RTK receiver and a correction service; see the accuracy page and the phone vs light bar vs autosteer vs RTK guide.