How does GPS Tracking work?

Depending on the version of iOS on your device, the device itself and available services, Track My Mileage takes advantage of Location Services which uses a combination of cellular, Wi-Fi, Bluetooth, and GPS to determine your location.

Note: Continued use of GPS running in the background can dramatically decrease battery life.

For devices running iOS 4:

  • iPod touch uses only Wi-Fi for Location Services (if a Wi-Fi network is available).
  • GPS is not available on original iPhone or iPad Wi-Fi.
  • iOS devices sold in China may use the term Wireless LAN (WLAN) instead of Wi-Fi. Not all China iPhone models support WLAN.
  • If you're not within a clear line of sight to GPS satellites, your device can determine your location using Wi-Fi. If you're not in range of any Wi-Fi, your device can determine your location using cellular towers.

For devices running iOS 5:

  • iOS devices without a cellular connection only use Wi-Fi for Location Services (if a Wi-Fi network is visible).
  • GPS is available on iPhone and iPad Wi-Fi + 3G models.
  • iOS devices sold in China may use the term Wireless LAN (WLAN) instead of Wi-Fi. Not all China iPhone models support WLAN.
  • If you're not within a clear line of sight to GPS satellites, your device can determine your location using crowd-sourced Wi-Fi and cell tower locations.

For devices running iOS 6:

  • iOS devices without a cellular connection use only Wi-Fi for Location Services (if a Wi-Fi network is available). At some time the app may rely on a Wi-Fi connection for region monitoring. If a device is passcode locked, this feature may be limited or inaccurate.
  • GPS is available on iPhone and iPad Wi-Fi + 3G models.
  • iPad (Wi-Fi + Cellular models): Verify that Cellular Data is on in Settings > Cellular Data, even if you aren't subscribed to a cellular data plan. This will allow your device to more accurately calibrate itself using network time and location information. In some instances, disabling a SIM PIN may be necessary.
  • iOS devices sold in China may use the term Wireless LAN (WLAN) instead of Wi-Fi. Not all China iPhone models support WLAN.
  • If you're not within a clear line of sight to GPS satellites, your device can determine your location using crowd-sourced Wi-Fi and cell tower locations.

For devices running iOS 7 and newer:

  • iOS devices without a cellular connection use only Wi-Fi for Location Services (if a Wi-Fi network is available). At some time the app may rely on a Wi-Fi connection for region monitoring. If a device is passcode locked, this feature may be limited or inaccurate.
  • GPS is available on iPhone and iPad Wi-Fi + 3G models.
  • iPad (Wi-Fi + Cellular models): Verify that Cellular Data is on in Settings > Cellular > Cellular Data, even if you're not subscribed to a cellular data plan. This will allow your device to more accurately calibrate itself using network time and location information. In some instances, disabling a SIM PIN may be necessary.
  • iOS devices sold in China may use the term Wireless LAN (WLAN) instead of Wi-Fi. Not all China iPhone models support WLAN.
  • If you're not within a clear line of sight to GPS satellites, your device can determine your location using crowd-sourced Wi-Fi and cell tower locations or iBeacons.

Improving GPS accuracy

GPS accuracy varies depending on the number of visible GPS satellites. Locating all visible satellites can take several minutes, with accuracy gradually increasing over time. Use these tips to improve GPS accuracy:

  • Ensure the date, time, and time zone are correctly set on the device in Settings > General > Date & Time. If possible, use Set Automatically.

    Important: Incorrect settings on your computer can sync to your device. Verify the date, time, and time zone on any computer that syncs with your device.
  • Verify that you have a cellular or Wi-Fi network connection. This allows the Assisted GPS (A-GPS) on the device to locate visible GPS satellites faster, in addition to providing initial location information using the Wi-Fi or cellular networks.

    Note: Microcells (sometimes called Femtocells) aren't supported with Location Services.
  • Maintain a clear view of the horizon in several directions. Keep in mind that walls, vehicle roofs, tall buildings, mountains, and other obstructions can block line of sight to GPS satellites. When this occurs, your device will automatically use Wi-Fi or cellular networks to determine your position, until the GPS satellites are visible again.
  • Restart your device.

Crowd-sourced Wi-Fi and cellular Location Services (iOS 5 and newer)

If Location Services is on, your device will periodically send the geo-tagged locations of nearby Wi-Fi hotspots and cell towers in an anonymous and encrypted form to Apple to augment Apple's crowd-sourced database of Wi-Fi hotspot and cell tower locations. In addition, if you're traveling (for example, in a car) and Location Services is on, a GPS-enabled iOS device will also periodically send GPS locations and travel speed information in an anonymous and encrypted form to Apple to be used for building up Apple's crowd-sourced road traffic database. The crowd-sourced location data gathered by Apple doesn't personally identify you.