Does Low Data Mode affect GPS tracking on iPhone?

The short answer

No. Low Data Mode is a network setting — it reduces how much data apps move in the background over a chosen Wi-Fi network or cellular plan. It has nothing to do with the GPS receiver, which works out a position from satellite signals rather than from anything traveling over Wi-Fi or a cellular connection. A route recorded with Low Data Mode switched on has exactly as many points, and the same accuracy, as one recorded with it off, because the two systems do not share any part of the pipeline that Low Data Mode is built to slow down.

What Low Data Mode actually targets

Low Data Mode is a per-network switch — it can be turned on for a specific Wi-Fi network or for a cellular plan, and it stays off for any network it was not enabled on. Where it is on, iOS holds back the everyday background traffic that apps generate on their own initiative: automatic content downloads, background app refresh over that network, and quality steps some apps take down a notch to move less data. None of that is about a GPS fix. It is aimed at apps quietly using a network in the background, not at a task like recording a route that was explicitly started and does not need a network connection to keep running.

Why GPS tracking does not run through that path

A recorded route comes from a chain that starts and ends inside the phone: satellite signals reach the GPS receiver, the receiver works out a position, and that position gets written to the track that is building up on the device. No network hop sits anywhere in that chain. This is the same reason a route keeps recording with no cell signal at all, covered in tracking a hike without cell service, and the same reason switching Wi-Fi off does not touch tracking either. Low Data Mode narrows what a phone sends and receives over a network it is connected to; a GPS fix is not something the phone sends or receives from anywhere, so there is nothing for the setting to narrow.

Where a network setting like this can still cost something

The parts of a hiking app that do depend on a network are the parts Low Data Mode can genuinely slow down. Syncing a finished route to the cloud, or an on-screen map pulling in new tiles as you scroll or walk into an area it has not loaded yet, both move data over whatever network is active, and Low Data Mode is built to hold exactly that kind of traffic back or defer it. None of it touches the track itself — the points, timestamps and altitude readings already saved to the phone are identical either way. The only thing that changes is whether something gets sent or fetched over the network right away, or waits for a moment when the setting is not limiting that particular connection.

Low Data Mode is not the same setting as Low Power Mode

The two get confused because both dial something back automatically, but they are not aimed at the same resource. Low Power Mode is about battery, and it turns down things like background app refresh, automatic downloads and some visual effects to stretch a charge. Low Data Mode is about network traffic, and it turns down background data use over a chosen network, independent of how much battery is left. A phone can have one on and the other off, both on, or both off, in any combination. Neither one disables Location Services or slows the GPS receiver, for the same underlying reason: recording a route is a request the app made explicitly, and both settings are built to hold back what a phone or an app does on its own, not what was directly asked for.

Things that trip people up

• Assuming any setting with "data" or "low" in the name must affect GPS — GPS position comes from satellites, not from cellular or Wi-Fi data, so a data-saving setting has no path to reach it.
• Turning Low Data Mode off mid-hike hoping to fix a track that looks wrong — the track was never affected by it, so the real cause is somewhere else, most often ordinary GPS noise under tree cover or near tall terrain.
• Expecting a route synced to the cloud to appear immediately with Low Data Mode on — the recorded track on the phone is complete and correct the moment it is saved; only the upload can wait for a less restricted connection.
• Mixing this setting up with Low Power Mode when troubleshooting battery instead of data usage — they save two different things and neither one touches tracking accuracy.

Where TrailCam fits in

TrailCam records a route from GPS in the background and does not need a network connection to do it, so Low Data Mode being on for a given network changes nothing about the points logged along the way. Cloud backup, part of the optional TrailCam Pro upgrade, is the one piece that moves data over a network — a route saved on the phone stays complete and available to replay or export as GPX 1.1 or CSV regardless of what any network setting is doing. TrailCam is free to download.