Pacer uses your phone’s GPS hardware to create a map of your outdoor walk, run or ride.

If the phone can’t maintain a reliable GPS signal, the route may be missing segments, appear as a straight line or never record at all.

The steps below will help you fix the problem on both iOS and Android.

How GPS route tracking works

• Phone GPS versus wearable data – Pacer’s route map comes from your phone’s GPS chip. 

  Wearables like Fitbit and Garmin do not share route data with Pacer – they usually provide only steps or calories. To get a map, record your activity with the phone or an Apple Watch that is connected to Apple Health. 

• Good GPS signal is essential – GPS signals are weak and can be blocked by buildings, tunnels, heavy tree cover or even metallic car window film. Google points out that GPS may report “signal lost” when you’re indoors or underground and that a low battery or faulty GPS unit can cause lost signal. Tall buildings and trees are also known to degrade accuracy. 
• Battery and power‑saving modes – Many phones turn off the GPS when the battery is low or when battery saver modes are enabled.  Low Power Mode on iOS disables background app refresh , and Android’s Battery Saver can pause GPS hardware.

General troubleshooting (all devices)

1. Start your activity outside and wait for a solid GPS fix. 

   Step outside and allow Pacer to acquire satellites before pressing “Start.”  A clear view of the sky is required.  Avoid tunnels, tall buildings and thick tree cover.  If you’re in a car, metallic window tint can block GPS signals. 

2. Hold the phone so the antenna is unobstructed. 

   Use a slim running belt, waistband or armband so the phone’s antenna isn’t blocked; A thin phone holder is recommended to prevent signal interference.  Removing bulky cases can also help. 

3. Keep your battery charged and phone cool. 

   Ensure the battery is above 20 % and the device is not overheating. Low battery and overheating can cause phones to turn off GPS or throttle background services. 

4. Encourage the GPS to activate. 

   If Pacer doesn’t show a GPS indicator, toggle GPS off and on or enable and disable Airplane Mode.  On Android, moving away from Wi‑Fi can force the phone to use GPS hardware. 

5. Restart the app and device. 

   Force‑quit Pacer and any other heavy apps, then relaunch it.  Restarting the phone often resolves transient GPS problems. 

6. Use the latest software. 

   Update Pacer and your phone’s operating system to the latest versions; updates often fix GPS and sensor bugs.  On Android you can turn on auto‑update in the Play Store ; on iOS check Settings > General > Software Update. 

7. Check your device type. 

   iPods and Wi‑Fi iPads don’t have a native GPS chip and rely on Wi‑Fi triangulation, so they cannot record accurate route maps.  Use an iPhone or Android phone with built‑in GPS instead.

iOS: fix missing or incomplete routes

Allow Pacer to access your location

1. Open Settings → Privacy & Security → Location Services. 
2. Turn on Location Services and scroll down to Pacer. 
3. Set access to “While Using the App” (or “Always” if available) and enable Precise Location.

Enable Background App Refresh

1. Open Settings → General → Background App Refresh. 
2. Ensure Background App Refresh is on and that Pacer is allowed. 
3. Turn off Low Power Mode, because it automatically disables background refresh.

Make sure iOS has a strong GPS fix

• Leave Wi‑Fi turned off at the start of your activity if you are outdoors; Wi‑Fi can introduce errors in GPS coordinates. 
• Toggle Airplane Mode or Wi‑Fi off and back on to refresh the phone’s radio. 
• Enable automatic date & time in Settings → General → Date & Time so recorded points aren’t timestamped incorrectly.

Reset sensors and update software

• Close Pacer and restart your iPhone. 
• Check for updates in Settings → General → Software Update. 
• If you use an Apple Watch, make sure Route Tracking is turned on (Watch app → Workout → Route Tracking) and that the watch has clear sky view during outdoor workouts.  Pacer receives route data via Apple Health; a weak GPS on the watch will result in missing segments.

Android: fix missing or incomplete routes

Enable location and high‑accuracy mode

• Open Settings → Location. 
• Turn on Use Location. 
• Tap Location Services or Location Accuracy and enable Improve Location Accuracy. 
• In some phones you can choose Mode → High Accuracy, which uses GPS, Wi‑Fi and mobile networks for the most precise location.

Grant Pacer precise location permission

1. Go to Settings → Apps → See all apps → Pacer. 
2. Tap Permissions and ensure Location is in the Allowed list. 
3. Choose Allow only while using the app and toggle Use precise location.

Turn off power saving modes and battery optimizations

• Open Settings → Battery and ensure Battery Saver is turned off. 
• Disable any app‑specific battery optimizations or “sleeping apps” features that pause background GPS or close Pacer.  Device‑specific guides (e.g., Samsung “Sleeping apps” or Xiaomi’s MIUI Battery Saver) may be needed – ensure Pacer is excluded from these lists.

Get a strong GPS signal

• Use Pacer outdoors and allow it time to lock onto satellites.  It's recommended to use a runner’s belt or thin holder so your phone’s antenna is not blocked. 
• Keep the phone’s battery above 20 % and avoid overheating; a warm phone may shut down services. 
• Move away from Wi‑Fi to encourage GPS hardware to activate. 
• Ensure you have an Internet connection: downloading assisted GPS data helps your phone quickly locate satellites.

Restart and update

• Restart your Android phone to refresh its radio and GPS hardware. 
• Update Pacer through the Play Store and enable auto‑update. 
• Check for system updates in Settings → System → Software Updates.

Understand approximate vs precise location

Some phones may show a blue dot on the map using Wi‑Fi or cellular networks, but this is only an approximate location. Such estimates are not sufficient for tracking workouts. Ensure “Precise location” is enabled and wait until GPS hardware has acquired satellites before starting your activity.

Additional tips

• Toggle GPS and Airplane Mode: quickly turning GPS or Airplane Mode off and on can reset the GPS radio. 
• Remove thick cases: metal or thick cases can block signals. 
• Disable Wi‑Fi auto‑join: staying on the edge of a Wi‑Fi network may delay GPS acquisition; move away from your home Wi‑Fi and rely on cellular data. 
• Check hardware issues: if your device cannot acquire a GPS signal even when fully charged and outside under a clear sky, the GPS hardware may be faulty; Google recommends testing with a GPS status app or contacting the device manufacturer.

Final check

1. You start your activity outdoors and wait for a strong GPS signal. 
2. Pacer has full location permission and, on iOS, Background App Refresh is enabled; on Android, battery optimization is disabled. 
3. Your phone’s battery is above 20 %, it’s not overheating, and you’re not under heavy tree cover or near tall buildings. 
4. Pacer is running the latest version, and your phone’s operating system is up to date. 
5. After your activity, the route map should show a continuous path without straight‑line jumps. If routes are still missing, gather logs and contact Pacer support.

Following these steps should help ensure Pacer records your GPS routes reliably so you can enjoy an accurate map of your outdoor activities.