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FusedLocationProviderClient.requestLocationUpdates not getting altitudes

I'm experiencing some strange behavior with our Android app using Fused location Provider Api.
In some devices this api is not returning the altitudes
I can check it on Moto G 2d generation but our users report the same behavior at least on Moto G 3d generation, Nexus 6 and Moto X Play. In the great majority of other devices altitudes are returning well so I'm pretty sure that my implementation of the Api is correct.
The funny part is that I realized that if I use android.location.LocationManager
, for example, like this
mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 500, 0, locationListener);
the app is starting to receive altitudes, not only on 'LocationListener' subscribed to 'LocationManager' but on LocationCallback of the Fused Location Provider Api as well.
But this breaks the optimization made by Fused location Provider Api and seems silly to use both apis.
I can experience similar behavior if I use both google maps and our app. While using google maps our app is receiving altitudes but when google maps is closed Fused Location Provider Api stops to send altitudes as well.
When I'm talking about not receiving altitudes I mean that location.hasAltitude() == false and location.getAltitude() == 0
This is my implementation to request location updates:
LocationServices.getFusedLocationProviderClient(context);
LocationRequest currentLocationRequest = new LocationRequest();
currentLocationRequest.setInterval(500)
.setFastestInterval(0)
.setMaxWaitTime(0)
.setSmallestDisplacement(0)
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
fusedLocationProviderClient.requestLocationUpdates(currentLocationRequest, locationCallback);
It seems to me that FusedLocationProviderClient is not turning on some hardware stuff on this devices, so may be a bug on this Api, but I didn't found any one else reporting that, except this similar behavior:
Nexus 6 Fused Location Provider getSpeed returns 0
Thanks.

Since hasAltitude() returns false there are parameters missing to the FusedLocationProvider that would make it possible to provide a confident altitude. This depends largely on the manufacturers setup and devices capabilities which is one of the reasons the Provider exists.
The reason could also be an insufficient GPS-lock or something else but since you could narrow it down to certain devices I would expect that not to be the issue.
You can try (as you already did) other location data sources and check if their results return an altitude, but keep in mind that that might be less consistent. My first try would be the old Location provider.
But there is no way for you to fix the misbehavior of the FusedLocationProvider it is a manufacturer config fail.

Android GPS location accuracy issue

I am working on gps tracking apps in android. Here is my code architecture:
BackgroundSyncService : A service class that is used for getting location update. Here GoogleApiClient is initialized and implements others Location related methods.
AppRunCheckerReceiver : A BroadcastReceiver class that will check if my BackgroundSyncService is running or not in a time interval. If it stopped then it start.
GpsEnableReceiver : A BroadcastReceiver it will fire if gps status changed. It will check if my BackgroundSyncService is running or not in a time interval. If it stopped then it start.
InternetConnectionStateReceiver : A BroadcastReceiver it will fire when internet status changed. It will check if my BackgroundSyncService is running or not in a time interval. If it is stopped, then it start.
In my BackgroundSyncService service I initialize the GoogleApiClient using this way:
public void setLocationLocationRequest() {
try {
googleApiClient = new GoogleApiClient.Builder(this).addConnectionCallbacks(this)
.addOnConnectionFailedListener(this).addApi(com.google.android.gms.location.LocationServices.API).build();
locationRequest = new LocationRequest();
locationRequest.setInterval(3000);
locationRequest.setFastestInterval(3000);
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
googleApiClient.connect();
} catch (Exception e) {
}
Here accuricy is LocationRequest.PRIORITY_HIGH_ACCURACY and interval is
locationRequest.setInterval(3000)
here is the GoogleApiClient implementation code.
This application GPS info section contains Latitude longitude and Accuracy parameter
My Findings: in onLocationChanged(Location location) method I check the accuracy of Location object in this way : location.getAccuracy(). Here if accuracy is less than 50 meter, then I accept it.
In 85% of the cases it working like a charm. It sending me exact location from GPS. But in 15% cases, it sending me inaccurate location like more >300 meter.
The 15% device are low cost China brand mobile.
My Questions:
How can i make accuracy level near 99%. Is there any problem on my code architecture?
Does GPS accuracy depends on device configuration? if YES then what can I do for low configuration device?
How Uber, Go-JEK etc. ride sharing apps works for all device? Is they have extra coding for GPS only?
My application is for Bangladesh. Here internet is slow. Is it has negative impact on GPS accuracy?
Thanks in advance for this thread. And also sorry for bad english.

How can i make accuracy level near 99%. Is there any problem on my code architecture?
This is real life scenario. You cannot ensure that all the location providers will work as expected. You should ask for best available position.
a) Does GPS accuracy depends on device configuration?
YES. Some devices may have older GPS chipsets which can only track GPS signals (USA) since there are other positioning systems like Galileo (Europe), GLONASS (Russia), QZSS (Japan) and Beidou (China). The more the chipset support for these types the more chance you get to track more satellite hereby position fix. Also TTFF (time to first fix) depends on how many channels do the gps receiver has.
b) If YES then what can i do for low configuration device?
Since this is a hardware issue, you cannot do anything here. But other location sources can compensate the lack of GPS data such as AGPS (aided gps), wifi and cellular positioning. Also there are some paid options which provides a database to locate your device using wifi access points and cellids (they claim that they provide best solution on wifi but i m not sure as I dont use it. you can check it out http://combain.com). Wifi and cellid also depends on how many wifi access point and cell tower available around and how far they are (signal strength). If you need 50m accuracy, cellular positioning has nothing to do but wifi has a chance to get closer to this value.
Some study results from 2009 [3]
3G iPhone w/ A-GPS ~ 8 meters
3G iPhone w/ wifi ~ 74 meters
3G iPhone w/ Cellular positioning ~ 600 meters
How Uber, Go-JEK etc. ride sharing apps works for all device? Is they have extra coding for GPS only?
They may have specific Location strategies but it will based on using other sources during GPS outage.
My application is for Bangladesh. Here internet is slow. Is it has negative impact on GPS accuracy?
Other answers claims that internet is not related to GPS. Yes it is true it is not related to GPS but location. AGPS uses internet to fetch 3 types of data (Satellite signals, almanac and ephemeris) which assist GPS to provide position fix faster. If ephemeris and almanac are outdated or the device moved several hundred km from the previous position fix then it is called cold start and takes around 12-15min without AGPS.
Fused location provider already knows how to provide best solution with these configurations, so you should bless it.
References:
[1] http://gpssystems.net/agps/
[2] http://gpsinformation.net/main/almanac.txt
[3]
https://communityhealthmaps.nlm.nih.gov/2014/07/07/how-accurate-is-the-gps-on-my-smart-phone-part-2/

First, (and second)
How can I make accuracy level near 99%. Is there any problem on my code architecture?
Does GPS accuracy depends on device configuration? If YES then what can I do for low configuration device?
Both - device configuration and code architecture, are important here. If you are already at an 85% success rate, the code architecture is alright I think.
As far as GPS goes, line-of-sight is an important factor when it comes to device configurations and accuracy.
Although a low cost mobile could return an accurate location with a clear line-of-sight. You can try running 2 cycles more/waiting to attain higher accuracy.
In a worst case scenario and for what its worth, you can also try retrieving location using the LocationManager and GPS provider technique which works as a fallback in the 15% just to compare and ensure you are using the most accurate location you can get.
Location Strategies put it as
In most cases, you'll get better battery performance, as well as more
appropriate accuracy, by using the Location Services API.
How Uber, Go-JEK etc. ride sharing apps works for all device? Is they have extra coding for GPS only?
They do work but not always with highest of accuracy for locations received within the app. If there are any location hacks for us developers, we need to find them, maybe a 5th page google search result :) or benefit from the open source environment. For me, best practices and android repo links suffice. You have already followed posts like Receive location updates
My application is for Bangladesh. Here Internet is slow. Is it has negative impact on GPS accuracy?
No relation between Internet and LocationManager + GPS_PROVIDER

Is Fused Location Provider good choice?

I am developing an application where I want to use Fused Location Provider. But I have some doubts, and couple of questions.
When GPS is off and I set priority to HIGH, does that mean that the GPS will be automatically turned on, or not?
Can I set UpdateLocation with Fused provider with HIGH priority on demand to save battery at least a little bit?
How can I know what Fused provider is using (is it a GPS or a network provider)?
And finally
Is Fused provider really the best choice for android location? Are there any negative points about it?
What is your opinion?
Thanks in advance.

When GPS is off and I set priority to HIGH, does that mean that GPS will be automatically turned on, or not?
No, it will not be turned on automatically. But if you use SettingsApi, will prompt a dialog to user and gives information that GPS is must be turned on. If user accepts it, the gps will be active automatically. Check the SettingsApi
How can I know what Fused provider is using (is it a GPS or a network provider)
If you use fused provider api with SettingsApi properly. It will make adequate the required settings for current location request.
Is Fused provider really the best choice for android location? Are there any negative points about it?
In my opinion, before fused provider you must deal with directly providers(Gps, network) But fused just asks you, "how accurate locations you wanna receive ?"

As in here https://developer.android.com/training/location/index.html stated very clearly that, the Google Play services location APIs are preferred over the Android framework location APIs (android.location) as a way of adding location awareness to your app. If you are currently using the Android framework location APIs, you are strongly encouraged to switch to the Google Play services location APIs as soon as possible. So I hope you got your answer.

I made a testing application for Gps, Wifi and Fused Location Provider and testing it for 2 days. It's better because it uses both of them and most of the time it's the one most accurate. Also, Gps data is a very noisy data that causes jittering, to solve this low-pass filter or other filters are used. One of the most successful filter used to get most accurate results is Kalman Filter. FusedLocationProvider use this filter same as RotationVector which is a fused sensor combines hardware and software. RotationVector uses accelerometer, gyroscope(if available), and magnetic field sensor to get and filter positition and azimuth data.
Location.getProvider for Gps with LocationManager returns "gps", Wifi returns "network", and FusedLocationProvider returns "fused".
When GPS is off and I set priority to HIGH, does that mean that the GPS will be automatically turned on, or not
Anything other than "Battery Saving" turns Gps on if available. This settings available on my Android 7.1.1 phone. Setting for location was different on previous versions of Android on user's side. As a developer to enable using Gps you should set mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
PRIORITY_HIGH_ACCURACY - Use this setting to request the most precise location possible. With this setting, the location services are more likely to use GPS to determine the location.
Setting Priority also determines battery use level too.
Can I set UpdateLocation with Fused provider with HIGH priority on demand to save battery at least a little bit?
Yes, you can set interval of location request in addition to priority.
mLocationRequest.setInterval(UPDATE_INTERVAL_IN_MILLISECONDS);
mLocationRequest.setFastestInterval(FASTEST_UPDATE_INTERVAL_IN_MILLISECONDS);
How can I know what Fused provider is using (is it a GPS or a network provider)?
Location from Wifi never returns true for Location.hasSpeed() but Gps returns almost always true if you are outdoors. Also location.getExtras() have satellites tag which you can check for satellites which is only available for Gps. Speed may not be correct if you are walking or as far i've read so far, i haven't tried this on car, when speed it less than 5km/h it's not very accurate. I mean if you are using FLP and last location data contains speed info it's definitely from Gps.
Are there any negative points about it?
As of Android 8.0 and above there is location retrieving limit if you do not use a Foreground Service or get location on foreground while app is not paused for both FLP and LocationManager.
Also FLP requires GooglePlayService to be available on user's device and it should be above a particular version. 10 or 11 depending on which one you use. This can be trouble if you wish to publish your apps on a country, for example China, that bans Google Play Services.

The existing answers don't say why the FusedLocationProvider is better.
It is better because the API fuses from more data sources (sensors, wifi, context, history) in an intelligent and battery-saving way. Also, Google is always improving it by adding more data sources. If your app uses it, you get those improvements for free.

GPS works better with google maps than my App android

I have an app in android using GoogleMaps API.
When i use google maps, I active gps and it find me so fast.
When i use my app, it takes some seconds, and if I'm in my house, gps dont find me. WHY ?
A short summary of my code:
locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
MyLocationListener = new MyLocationListener();
locationManager.requestLocationUpdates(
LocationManager.GPS_PROVIDER,
7000,
5,
MyLocationListener
);
Thx for answers and sorry for my poor english
EDIT
Thx for answers ! the problem is that i dont want to use network provider. Wifi is exelent, and 3g have a 400 meters error jejeej.
I only want to know, why google maps, using GPS, find me in 1 second with perfect position Although I stay in a house.
Your answer is "use coarse locate". If google maps use network providers befor gps, its impossible he find me so fast. :(

GPS is using satelites, When you are indoor it can't get the signal from the satelites hence it can't find location (can't get a fix).
The GPS needs signals from at least 4 satelites to get a proper fix, that usually takes a few seconds, once you already have a fix you can maintaine it very easly. therfore if you are using google maps it will get you a fix faster.
To get a better understand on how GPS works, check this link
You might want to use different location approachs for getting location indoor (coarse location could be the answer). I would also consider using the fused location by Google play services, it gives you a wrap up on the location providers and get you location based on what avilable at the time (meaning GPS, coarse - wifi or network).

You should try using Coarse locates for a quick locate followed by a fine locate to have a more accurate location. The coarse locate is usually very fast, while the fine one takes more time.
Basically, the idea is to do multiple locates and overriding the less accurate ones by the newer and more accurate locates.
You can find more info on the Android dev doc: http://developer.android.com/guide/topics/location/strategies.html
EDIT: if Google Maps is able to find you so fast, it is because you are not moving and they use the knowledge of the last location. Please read the above link that gives a lot of useful information for Location strategies (and it works very well).

I do not get geofence notifications

I'm writing an Android application that notifies the user when he enters a specific region. For this I used the Geofence API from Android.
I have tried Google's GeofenceDetection sample, and The application does not get notified at all.
I call addGeofences, and receive onAddGeofencesResult notification with statusCode 0, so all seems to be working fine, but when I walk (or drive) in and out of the geofence (with radius 5m or 50m) nothing happens.
I use Nexus4 and Eclipse - both updated to latest versions.
Why don't I get geofence notifications?

I've found that the GeoFencing API never intelligently retrieves locations from the GPS hardware. The GeoFence API will observe the most accurate location available from the OS or if no location is currently available, it will cause a location to be calculated from Wifi / Cellular. (which sucks because cellular is wildly inaccurate and wifi is often unavailable)
So to get at all responsive or accurate results out of the Geofencing API you have to set up your Geofences and then poll the GPS hardware on an interval, not even doing anything with the result received, so that under the surface you are providing worthwhile data to the OS.
This behaviour is not documented- thanks Google!