Required Reading
Plugin Version
5.0.5
Mobile operating-system(s)
Device Manufacturer(s) and Model(s)
Samsung A36, iPhone 17 pro, iPhone 13, Honor 8 lite
Device operating-systems(s)
Android 15, IOS 26.3
What do you require assistance about?
We recently migrated from v4 to v5 (5.0.5). After extensive testing, we found that useKalman: true causes
location.odometer to always return 0.0, regardless of actual movement.
Our goal: Reduce GPS jitter accumulation on the odometer when the device is stationary. During a 20-minute stationary period, the odometer accumulated ~70m of false distance due to GPS drift, even with good accuracy readings (6-8m).
What we tested (5 tests on Samsung A36, Android 15):
| Test |
useKalman |
odometerUseKalmanFilter |
maxImpliedSpeed |
Odometer |
Tracking |
| 1 |
not set (default true) |
not set (default true) |
not set |
0.0 always |
Poor (12 points in 6h) |
| 2 |
false (explicit) |
false (explicit) |
not set |
0.0 always |
Better (22 points) |
| 3 |
false |
false |
not set |
Working |
Working |
| 4 |
true |
false |
60.0 |
0.0 always |
Degraded |
| 5 |
false |
true |
60.0 |
Working |
Working |
Key findings:
- useKalman: true breaks location.odometer completely (always 0.0), even when odometerUseKalmanFilter: false
- odometerUseKalmanFilter: true works correctly when useKalman: false
- Tests 1 and 2 both had odometer=0 because v5 defaults useKalman to true — we initially didn't realize omitting theparameter meant Kalman was still active
Our questions:
- Is useKalman: true expected to affect location.odometer even when odometerUseKalmanFilter is set independently?The documentation says they are independent Kalman instances.
- What is the recommended configuration to minimize stationary GPS jitter on odometer while keeping accurate tracking? Specifically, is there a way to prevent odometer accumulation when isMoving: false?
- Is this a bug in 5.0.5 that useKalman: true zeroes out the odometer?
[Optional] Plugin Code and/or Config
bg.BackgroundGeolocation.ready(bg.Config(
reset: true,
geolocation: bg.GeoConfig(
desiredAccuracy: bg.DesiredAccuracy.navigation,
distanceFilter: Platform.isIOS ? 100 : 50,
stopTimeout: 5,
geofenceModeHighAccuracy: true,
disableElasticity: false,
elasticityMultiplier: Platform.isIOS ? 1.5 : 1,
useSignificantChangesOnly: false,
disableLocationAuthorizationAlert: true,
locationAuthorizationRequest: 'Always',
showsBackgroundLocationIndicator: true,
filter: bg.LocationFilter(
odometerAccuracyThreshold: 100,
useKalman: false, // true breaks odometer
odometerUseKalmanFilter: true,
maxImpliedSpeed: 60.0,
),
),
activity: bg.ActivityConfig(
activityRecognitionInterval: 0,
stopOnStationary: false,
disableStopDetection: false,
triggerActivities: 'on_foot, walking, running, in_vehicle, on_bicycle',
),
http: bg.HttpConfig(
url: API_URL,
method: 'POST',
autoSync: true,
batchSync: true,
maxBatchSize: 1,
),
app: bg.AppConfig(
schedule: schedule,
stopOnTerminate: false,
startOnBoot: true,
enableHeadless: true,
heartbeatInterval: 300,
),
logger: bg.LoggerConfig(
debug: false,
logLevel: bg.LogLevel.error,
),
));[Optional] Relevant log output
bg.BackgroundGeolocation.ready(bg.Config(
reset: true,
geolocation: bg.GeoConfig(
desiredAccuracy: bg.DesiredAccuracy.navigation,
distanceFilter: Platform.isIOS ? 100 : 50,
stopTimeout: 5,
geofenceModeHighAccuracy: true,
disableElasticity: false,
elasticityMultiplier: Platform.isIOS ? 1.5 : 1,
useSignificantChangesOnly: false,
disableLocationAuthorizationAlert: true,
locationAuthorizationRequest: 'Always',
showsBackgroundLocationIndicator: true,
filter: bg.LocationFilter(
odometerAccuracyThreshold: 100,
useKalman: false, // true breaks odometer
odometerUseKalmanFilter: true,
maxImpliedSpeed: 60.0,
),
),
activity: bg.ActivityConfig(
activityRecognitionInterval: 0,
stopOnStationary: false,
disableStopDetection: false,
triggerActivities: 'on_foot, walking, running, in_vehicle, on_bicycle',
),
http: bg.HttpConfig(
url: API_URL,
method: 'POST',
autoSync: true,
batchSync: true,
maxBatchSize: 1,
),
app: bg.AppConfig(
schedule: schedule,
stopOnTerminate: false,
startOnBoot: true,
enableHeadless: true,
heartbeatInterval: 300,
),
logger: bg.LoggerConfig(
debug: false,
logLevel: bg.LogLevel.error,
),
));
Required Reading
Plugin Version
5.0.5
Mobile operating-system(s)
Device Manufacturer(s) and Model(s)
Samsung A36, iPhone 17 pro, iPhone 13, Honor 8 lite
Device operating-systems(s)
Android 15, IOS 26.3
What do you require assistance about?
We recently migrated from v4 to v5 (5.0.5). After extensive testing, we found that useKalman: true causes
location.odometer to always return 0.0, regardless of actual movement.
Our goal: Reduce GPS jitter accumulation on the odometer when the device is stationary. During a 20-minute stationary period, the odometer accumulated ~70m of false distance due to GPS drift, even with good accuracy readings (6-8m).
What we tested (5 tests on Samsung A36, Android 15):
Key findings:
Our questions:
[Optional] Plugin Code and/or Config
[Optional] Relevant log output
bg.BackgroundGeolocation.ready(bg.Config( reset: true, geolocation: bg.GeoConfig( desiredAccuracy: bg.DesiredAccuracy.navigation, distanceFilter: Platform.isIOS ? 100 : 50, stopTimeout: 5, geofenceModeHighAccuracy: true, disableElasticity: false, elasticityMultiplier: Platform.isIOS ? 1.5 : 1, useSignificantChangesOnly: false, disableLocationAuthorizationAlert: true, locationAuthorizationRequest: 'Always', showsBackgroundLocationIndicator: true, filter: bg.LocationFilter( odometerAccuracyThreshold: 100, useKalman: false, // true breaks odometer odometerUseKalmanFilter: true, maxImpliedSpeed: 60.0, ), ), activity: bg.ActivityConfig( activityRecognitionInterval: 0, stopOnStationary: false, disableStopDetection: false, triggerActivities: 'on_foot, walking, running, in_vehicle, on_bicycle', ), http: bg.HttpConfig( url: API_URL, method: 'POST', autoSync: true, batchSync: true, maxBatchSize: 1, ), app: bg.AppConfig( schedule: schedule, stopOnTerminate: false, startOnBoot: true, enableHeadless: true, heartbeatInterval: 300, ), logger: bg.LoggerConfig( debug: false, logLevel: bg.LogLevel.error, ), ));