GPS Settings
What are the recommended GPS settings
MyOMaps is based on MyTracks which provides significant control of the GPS settings. The default settings are the best for MyOMaps. But if you want to try some options, following is some discussion on this topic.
You will need to be running the Android version of MyOMaps (full version). Under “Settings > Recording” the behaviour of the track recording can be adjusted by changing:
- Location Frequency
- Min Distance
- GPS Accuracy
Location Frequency
Location frequency controls how often a track point is recorded from the GPS.
There are specific time intervals available from 2 seconds to 30 minutes.
There are also three “non-specific” settings:
- Adapt for Battery
- Adapt for Accuracy
- Smallest.
Smallest:
This is the recommended option. It means that the GPS provides updates to the App with no minimum time gap nor any minimum distance between points. (Gets all updates from the GPS are provided with no min time and no min distance). Note that the App does then ignore points with insufficient accuracy or within the MinDistance setting (see below).
Adapt for Battery:
This option is to save battery life. It sets a minimum interval of 30 secs and min distance 5 m for GPS updates. (Again the App will filter out points that of insufficient accuracy or are closer than the MinDistance setting below)
Adapt for Accuracy:
This option aims to set a variable time interval between readings from the GPS based upon how frequently the GPS is providing new data points. It initially sets a minimum interval of 0; and a min distance of 0, but then it adapts the minimum interval to be half the time between the last two points – and keeps adapting. That is if the GPS provides two data points 20 seconds apart, the app will only allow the GPS to send another data point at least 10 seconds later (within the bounds of 1 and 30 seconds).
GPS Accuracy
When the GPS records a location it also provides an accuracy measurement. (This is also shown on the screen by the size of the blue circle).
Minimum accuracy settings can be: 10m to 5000m with a recommended 200m.
When the GPS returns a location to the App (no sooner than the required minimum time) the reading is check for accuracy. If the point has an accuracy worse than the minimum, the point is ignored.
The “fine print”:
Google defines accuracy as the radius of 68% confidence. In other words, if you draw a circle centered at this location's latitude and longitude, and with a radius equal to the accuracy, then there is a 68% probability that the true location is inside the circle.
In statistical terms, it is assumed that location errors are random with a normal distribution, so the 68% confidence circle represents one standard deviation. Note that in practice, location errors do not always follow such a simple distribution.
This accuracy estimation is only concerned with horizontal accuracy, and does not indicate the accuracy of bearing, velocity or altitude if those are included in this Location.
Minimum Distance
The minimum distance between recorded track points can be set to be between 1m and 100m with 5 m being recommended.
The App does not record a track point if the distance of the current location is < min distance from the last recorded point.
Conclusion/Summary:
In summary, the flow of the logic is:
- The GPS is set to return a location to the App only after a minimum time (Set by “Location Frequency”)
- The App then checks the accuracy of the location and discards if not good enough”(Set by “GPS Accuracy”)
- The App then checks if the point is far enough away from the previously recorded point and discards it if not (Set by “Min Distance”).
Note that Max Distance is a setting that does not relate to the recording of the GPS track. It relates to the statistics of a “segment”.
MyOMaps is based on MyTracks which provides significant control of the GPS settings. The default settings are the best for MyOMaps. But if you want to try some options, following is some discussion on this topic.
You will need to be running the Android version of MyOMaps (full version). Under “Settings > Recording” the behaviour of the track recording can be adjusted by changing:
- Location Frequency
- Min Distance
- GPS Accuracy
Location Frequency
Location frequency controls how often a track point is recorded from the GPS.
There are specific time intervals available from 2 seconds to 30 minutes.
There are also three “non-specific” settings:
- Adapt for Battery
- Adapt for Accuracy
- Smallest.
Smallest:
This is the recommended option. It means that the GPS provides updates to the App with no minimum time gap nor any minimum distance between points. (Gets all updates from the GPS are provided with no min time and no min distance). Note that the App does then ignore points with insufficient accuracy or within the MinDistance setting (see below).
Adapt for Battery:
This option is to save battery life. It sets a minimum interval of 30 secs and min distance 5 m for GPS updates. (Again the App will filter out points that of insufficient accuracy or are closer than the MinDistance setting below)
Adapt for Accuracy:
This option aims to set a variable time interval between readings from the GPS based upon how frequently the GPS is providing new data points. It initially sets a minimum interval of 0; and a min distance of 0, but then it adapts the minimum interval to be half the time between the last two points – and keeps adapting. That is if the GPS provides two data points 20 seconds apart, the app will only allow the GPS to send another data point at least 10 seconds later (within the bounds of 1 and 30 seconds).
GPS Accuracy
When the GPS records a location it also provides an accuracy measurement. (This is also shown on the screen by the size of the blue circle).
Minimum accuracy settings can be: 10m to 5000m with a recommended 200m.
When the GPS returns a location to the App (no sooner than the required minimum time) the reading is check for accuracy. If the point has an accuracy worse than the minimum, the point is ignored.
The “fine print”:
Google defines accuracy as the radius of 68% confidence. In other words, if you draw a circle centered at this location's latitude and longitude, and with a radius equal to the accuracy, then there is a 68% probability that the true location is inside the circle.
In statistical terms, it is assumed that location errors are random with a normal distribution, so the 68% confidence circle represents one standard deviation. Note that in practice, location errors do not always follow such a simple distribution.
This accuracy estimation is only concerned with horizontal accuracy, and does not indicate the accuracy of bearing, velocity or altitude if those are included in this Location.
Minimum Distance
The minimum distance between recorded track points can be set to be between 1m and 100m with 5 m being recommended.
The App does not record a track point if the distance of the current location is < min distance from the last recorded point.
Conclusion/Summary:
In summary, the flow of the logic is:
- The GPS is set to return a location to the App only after a minimum time (Set by “Location Frequency”)
- The App then checks the accuracy of the location and discards if not good enough”(Set by “GPS Accuracy”)
- The App then checks if the point is far enough away from the previously recorded point and discards it if not (Set by “Min Distance”).
Note that Max Distance is a setting that does not relate to the recording of the GPS track. It relates to the statistics of a “segment”.