Tracking stops

[Kris Buelens]

Another really annoying problem.

Android become moren an more clever to save battery.  If one doesn't do anything, Android puts GPS E in sleep mode when the screen goes off.

I detected (and still detect) it the hard way: coming home without a useful track.

Since quite some years, I know I have to place GPS E in Android's exception list for power saving.

But still every now and then tracking stops.  Yesterday (31 Aug) our bike trip was perfectly logged. 

But, a week ago (22 Aug), also on my bike (not a motorbike) with my phone in my pocket (like yesterday), many holes in the track

Remark 1: driving through really open space there, no trees, no buildings, but only one signal in that nature area.  Note for the 2: I put on my mobile as to check our path with google maps.  A while later -after being sure we where right- I stopped google Maps, probably I turned off the screen, and hops, GPS E stopped logging.  We entered a museum, and a bit expected a trackpoint (3) far away from where we were.  (expected).  On our path back home, same story, I use Google Maps to find my way through the streets for a while and tracking OK, turned it off and also no good tracking anymore.

Before you say -what I accept- no GPS E problem I still have remarks

• Would it be possible for GPS E to help its users, by that it would tell Android "don't put me in sleep"?
• Can other people on this group explain what happens with my phone?

Yesterday before starting our trip, I verified Android's settings for GPS E.  It was indeed still on the list for "no power optimalisation".  But, I turned it once on for power optimalisation and then back off.

A few months ago I detected another setting, after having turned on "developers mode" the list of "Stand-by-apps".  Months ago, I changed the state for GPS E from RARE to ACTIVE.  At that time I thought it helped, but not always (cfr the holes last week).  So I verified that too yesterday.  But in that list GPS E has now EXEMPTED as state, and is disabled, so I can't change it.  I guess being on the list for "no power optimisation", causes this EXEMPTED (what makes sense indeed).

But, why these holes on 22 Aug?

(and: track of  10 Aug: OK, 19 Aug: holes, 19 Jul OK)

(and, except for Yesterday, I didn't check nor changed the Android settings)

P.S. the hole exits as well in GPS E when displaying the track there, so it is not an export problem.

[mic...@mictale.com]

Let's get the obvious out of the way: If you long tap on the app icon on your desktop and select App Info and then Permissions, are the background permissions set to "Allow while the app is running in the background"?


Regards, Michael
mictale.com/ms
--

> On Sep 1, 2024, at 6:48 AM, Kris Buelens <kris.b...@gmail.com> wrote:
>
> Another really annoying problem.
>
> Android become moren an more clever to save battery. If one doesn't do anything, Android puts GPS E in sleep mode when the screen goes off.
>
> I detected (and still detect) it the hard way: coming home without a useful track.
>
> Since quite some years, I know I have to place GPS E in Android's exception list for power saving.
>

> But still every now and then tracking stops. Yesterday (31 Aug) our bike trip was perfectly logged. <noHoles.JPG>
>
> But, a week ago (22 Aug), also on my bike (not a motorbike) with my phone in my pocket (like yesterday), many holes in the track<Holes.JPG>

>
> Remark 1: driving through really open space there, no trees, no buildings, but only one signal in that nature area. Note for the 2: I put on my mobile as to check our path with google maps. A while later -after being sure we where right- I stopped google Maps, probably I turned off the screen, and hops, GPS E stopped logging. We entered a museum, and a bit expected a trackpoint (3) far away from where we were. (expected). On our path back home, same story, I use Google Maps to find my way through the streets for a while and tracking OK, turned it off and also no good tracking anymore.
>
> Before you say -what I accept- no GPS E problem I still have remarks
> •
> Would it be possible for GPS E to help its users, by that it would tell Android "don't put me in sleep"?
> • Can other people on this group explain what happens with my phone?
> Yesterday before starting our trip, I verified Android's settings for GPS E. It was indeed still on the list for "no power optimalisation". But, I turned it once on for power optimalisation and then back off.
> A few months ago I detected another setting, after having turned on "developers mode" the list of "Stand-by-apps". Months ago, I changed the state for GPS E from RARE to ACTIVE. At that time I thought it helped, but not always (cfr the holes last week). So I verified that too yesterday. But in that list GPS E has now EXEMPTED as state, and is disabled, so I can't change it. I guess being on the list for "no power optimisation", causes this EXEMPTED (what makes sense indeed).
> But, why these holes on 22 Aug?
> (and: track of 10 Aug: OK, 19 Aug: holes, 19 Jul OK)
> (and, except for Yesterday, I didn't check nor changed the Android settings)
>
> P.S. the hole exits as well in GPS E when displaying the track there, so it is not an export problem.
>

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> <Holes.JPG><noHoles.JPG>

[John Bernal]

In my phone I have to disable the battery saver for the app to work in background. I have version 4.5.28 however sin the last update the tracking does not even start, the app gets fix but the tracking never starts. I have wiped appa data, reinstalled, but noting changes.

[mic...@mictale.com]

This sounds very much like a permission problem. Please chek your location permissions as described below.

Regards, Michael
mictale.com/ms
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[Kris Buelens]

I think it is OK, but I don't understand the way Android informs me.

A problem also is that my Android speaks Dutch, so I added some translations in my screenshots.

Here the first screen I copied after tapping in its icon and asking for "i", info

 Location thus always permitted, not really the text you suggest: "Allow while the app is running in the background"

Now, I also went a bit further than the screen above: I asked for "all permissions", and get this screen

That seemed promising, I'd try to add the last one, but when I tap on it, I simply get extra information, no way to change anything

And it isn't clear if the permission is granted.  I'd say it is not as "Camera" is also in the list, and in the previous screen it is mentioned as not permitted.

So, I went to Android's settings to find "manage permissions" (maybe not the exact English term, in Dutch "machtigingsbeheer"). 

There I can find "location", but only 1 setting, not the 3 in previous screen, 

I open Location and select GPS E

So, might there be other settings hidden for me?

( I did turn on "developers-modus" )

And, the basic question: could GPS E check if its settings are OK?

[Gonzalo Ortega]

Greetings, I have the same problem, my cell phone is a Tecno Camon Pova Pro 5G and I have noticed the following situations: while the application has the tracking running in the foreground, with the active option of keeping the screen always on and the map environment active , the application tracks without problems, the only detail is that if I want to take photos, within the tracking I have to go back, there the signal is lost, it finds it again and I have to wait for the satellites to link again to continue with the tracking, I have also noticed that the tracking message in progress only appears 2 or 3 times after locking the screen, the moment the screen locks or the application is no longer with the tracking map open, it stops tracking immediately I would like you to solve these problems please, the application is very good

[Kris Buelens]

Strange things still happen to me:

3 weeks ago we went to France for 5 days: GPS Essentials worked perfectly well, no periods without signal (also while in my car all was OK).

I was happy.  

But last week, I went for a 13km e-bike trip.  Half way, somewhere in a nature area, I decided to make a track with GPS E.  Back home, disappointment: 3 trackpoints got collected: at the start, midway, and when I turned it off back home.  Most of the time, I was in an area with lots of agricultural fields, quite open to the sky, not in a forest, not surrounded by buildings, phone in a pocket of my trousers.  When driving by car, my phone is often in the same position, and I'd say it's worse as that is inside a metal car.

Kris Buelens
-----------------------------------------------------------------------

Op wo 16 okt 2024 om 16:11 schreef Gonzalo Ortega <geosco...@gmail.com>:

To view this discussion on the web visit https://groups.google.com/d/msgid/gpsessentials/ac5ad95d-a2d0-4ac7-ac42-23b935d7bc36n%40googlegroups.com.

[mic...@mictale.com]

Sorry for this bad experience. Android is getting increasingly "smart" about background processing and I'm having a hard time to catch up.

Which version of Android are you'all using? From the screenshots it looks like pre-12 with no "allow in background" option.

The other thing to look out for is the tracking icon in the notification tray (the paw). It should be visible all the time between start and stop/pause tracking.

Finally, GPS Essentials adds an event every time you start or stop tracking. The messages read "Track recording started" and "Track Recording Stopped". Do you get the second event? What is the message in the second event saying? Is the timestamp of the second event when you actually stopped tracking or does tracking stop premature?


Regards, Michael
mictale.com/ms
--

> On Oct 16, 2024, at 8:58 AM, Kris Buelens <kris.b...@gmail.com> wrote:
>
> Strange things still happen to me:
> 3 weeks ago we went to France for 5 days: GPS Essentials worked perfectly well, no periods without signal (also while in my car all was OK).
> I was happy.
> But last week, I went for a 13km e-bike trip. Half way, somewhere in a nature area, I decided to make a track with GPS E. Back home, disappointment: 3 trackpoints got collected: at the start, midway, and when I turned it off back home. Most of the time, I was in an area with lots of agricultural fields, quite open to the sky, not in a forest, not surrounded by buildings, phone in a pocket of my trousers. When driving by car, my phone is often in the same position, and I'd say it's worse as that is inside a metal car.
>
> Kris Buelens
> -----------------------------------------------------------------------
>
>
> Op wo 16 okt 2024 om 16:11 schreef Gonzalo Ortega <geosco...@gmail.com>:
> Greetings, I have the same problem, my cell phone is a Tecno Camon Pova Pro 5G and I have noticed the following situations: while the application has the tracking running in the foreground, with the active option of keeping the screen always on and the map environment active , the application tracks without problems, the only detail is that if I want to take photos, within the tracking I have to go back, there the signal is lost, it finds it again and I have to wait for the satellites to link again to continue with the tracking, I have also noticed that the tracking message in progress only appears 2 or 3 times after locking the screen, the moment the screen locks or the application is no longer with the tracking map open, it stops tracking immediately I would like you to solve these problems please, the application is very good
> El martes, 3 de septiembre de 2024 a las 14:57:48 UTC-4, kris.b...@gmail.com escribió:
> I think it is OK, but I don't understand the way Android informs me.
> A problem also is that my Android speaks Dutch, so I added some translations in my screenshots.
> Here the first screen I copied after tapping in its icon and asking for "i", info
>

> Location thus always permitted, not really the text you suggest: "Allow while the app is running in the background"
>
> Now, I also went a bit further than the screen above: I asked for "all permissions", and get this screen
>

> That seemed promising, I'd try to add the last one, but when I tap on it, I simply get extra information, no way to change anything
> And it isn't clear if the permission is granted. I'd say it is not as "Camera" is also in the list, and in the previous screen it is mentioned as not permitted.
>
> So, I went to Android's settings to find "manage permissions" (maybe not the exact English term, in Dutch "machtigingsbeheer").
> There I can find "location", but only 1 setting, not the 3 in previous screen,
> I open Location and select GPS E
>
>

> To view this discussion on the web visit https://groups.google.com/d/msgid/gpsessentials/CAHyxymL-ODJc0P53BBJL12zA%3DwzA3KffkFHP5%3DPoOBS9Lhqu%3DA%40mail.gmail.com.

[Kris Buelens]

I did delete that last back track... yesterday I did regret that
fact, I wanted to look indeed.
I do indeed sometimes keep an eye on the small tracking icon in
Andoid's status bar. But, when I had problems, most of the time
tracking restarted when I turned on screen power, so if the icon would
have disappeared, I would have noticed.

But, what puzzles me most is that everything ran fine these days in
France. And with my most recent bike trip it failed.

I know Android can remove permissions after long time no used app.
But here we speak about maximum 3 weeks.
Oh no: last day in France was 20 Sept and another bike trip with my
wife on 5 October. Perfect as well: I started GPS E at home, drove by
car to our bike starting point, then our biking, and only turned if
off back when back home (11:51 to 18:32)
The day with the failure was 10 October, 5 days, so Android should not
have taken permissions away. I turned it on roughly 5km from home, so
maybe 15 minutes, battery problems not expected, surely compared to
our trip on 5 oktober, almost 7 hours on the phone's battery.

The bike trip that failed was with an e-Bike, the trip with my wife,
she used the e-Bike, I an old, non-electric, one. The phone both
times in my trouser's pocket. Could an e-bike cause problems? The
e-bike's battery is approx 30cm from my trousers.

My Phone is a bit old by today's standards (but, I hate to replace
things that still work fine, so still my Samsung A40), hence an old
Android: V11
Attached the 5 Oct image, just perfect (the blue parts are biking)

Oh yes, in June we also went to France, and I had some problems some
days. I could extract such a track, in any format you want. The
second attachment is of 10 June, very bad. One can see there that
much of the time there were big "jumps", a tracking point each 5 to 10
minutes (and a very bad start), some periods every 5 seconds as
expected.

Kris Buelens,
--- VM/VSE consultant, Belgium ---
-----------------------------------------------------------------------

Op do 17 okt 2024 om 19:56 schreef <mic...@mictale.com>:

> To view this discussion on the web visit https://groups.google.com/d/msgid/gpsessentials/D574272F-AC5D-45EF-90A1-3AB292D5D27B%40mictale.com.

[Gonzalo Ortega]

Yes, I always keep in mind that the pin is in the notification tray, although I have noticed that it is there for a certain time and then disappears, to be more precise, after 3 manual blocks on my cell phone, the pin disappears from the notifications, Regarding the messages at the beginning of the tracking, if I get the recording message of tracking started, later when it blocks or the application is not in the foreground it loses the signal, but that does not prevent the cell phone from continuing tracking, when I stop the I track if I get the tracking stopped recording message.

[Gonzalo Ortega]

When the GPS loses signal, the cell phone does not detect it as a stop to the tracking, it just does not mark anything, if I have the program opened again and it receives a signal again, the tracking continues from there, but all the intermediate points are lost, it comes out as a straight line, signal loss is not an event recognized as a tracking stop,

[Kris Buelens]

New e-bike trip to my bakery today and I made a test.

• I started a new trip halfway (when I thought about making this test).  I started GPS E and walked a few steps until I saw GPS E had a real track (about 7 meters) then turn off the screen, phone in pocket, biking.  A few km further: I looked and found a perfect track.
• A while after leaving the bakery, I stopped this track, stopped GPS E completely, then started a new track (located under a tree, but one without many branches), turned the screen off and immediately started biking  Again after a while I stopped and had a look: again a good track.
• Then in a rural area, under trees, on a small and a bit sunken road, I started a new track, turned the screen off directly, and started biking.  At home: a failed track, one straight line.

Note: I think that when I say 'turn the screen off' it also means I closed GPS E's window.  That's how I usually work: afraid that some bad finger action would cause the tracking to stop, I close GPS E's screen before doing something else or turning screen off.  But, I'm only 99% sure I proceeded like this in all 3 tests.

So, maybe when the location services do not yet have a position and one send GPS E to the background things go wrong.  Just a guess, but that was what I tested.

I saved all 3 tracks, in GPX and MFT format.  The bad one looks like this (after processing by my fix tool that changes RTEPT to TRKPT and then splits at <trkpt> and some other tags)

<metadata>
<name>Track-241019-145212</name><desc /><time>2024-10-19T12:52:12.336Z</time></metadata>
<wpt lat="50.811783" lon="4.5546155"><ele>148.0</ele><speed>0.78999996</speed><time>2024-10-19T13:03:39.000Z</time>
<name>Track Recording Stopped</name><desc>Recording stopped at 11'22" because the user stopped it after 2.53km (40.0m gain).</desc></wpt>
<trk>
<name>Tracking android:ecb89d991f160f13</name><desc>Tracking recently started 19/10/2024 14:52</desc><number>280232</number>
<trkseg>
<trkpt lat="50.78904" lon="4.554475"><ele>108.0</ele><speed>0.28</speed><time>2024-10-19T12:52:17.000Z</time></trkpt>
<trkpt lat="50.811783" lon="4.5546155"><ele>148.0</ele><speed>0.78999996</speed><time>2024-10-19T13:03:39.000Z</time></trkpt></trkseg></trk></gpx>

All 3 tracks in GPS Track Editor look like this

The orange one is the first (yes, it contain an almost straight section: that road there is straight)

The green curly one is the second track

The green at the top, a bit wider, is the 3th, bad, one

Kris Buelens,
     --- VM/VSE consultant, Belgium ---
-----------------------------------------------------------------------

Op za 19 okt 2024 om 00:44 schreef Gonzalo Ortega <geosco...@gmail.com>:

To view this discussion on the web visit https://groups.google.com/d/msgid/gpsessentials/9e92eea2-15c2-4ac0-9adb-23e6d02eaec5n%40googlegroups.com.

[Kris Buelens]

Oh yes, I had some other idea, it proves that GPS E is not the only affected thing. I didn't forbid Google to collect  location history.  So I looked at it.

I think that Android is working a bit differently for its location services when a GPS tracking App is active.  Without it, Googles' location history is not precise at all, many straight lines, jumps from here to there, several KM apart.  When a tracker is active, google becomes precise too.

And I already wrote that my GPS E track of June 10 was very bad: 

• 16 trackpoints logged between 2024-06-10T07:09:28.606Z and 2024-06-10T10:21:25.000Z  
• GPS E's message:<name>Track Recording Stopped</name><desc>Recording stopped at 3h11' because the user stopped it after 172km (335m gain).

Just now I had a look at June 10 in my Google location history: it is bad too.  It is a good example as it spans a long time and distance; with shorter trips, Google's graph isn't showing many points.

Here what Google shows, and I added the GPS E track and yet another track (see below) on the same image

Google and GPS E correspond closely, not a surprise as both are collected by my phone.  The 3the one: it is perfect, our actual route.

How come I've got a 3'th one: well, as I often have problems with GPS E that every so often produces bad tracks (with these big holes in collected points), I spent some money to buy another GPS logger (Renkforce), that I hang on a ribbon around my neck.  On June 10, that track was almost perfect as can be seen above.  

Why still looking at GPS E then?  Well that Renkforce can be bad too, it also often loses GPS signals and behaves very badly when trees or buildings are around.  Maybe not a surprise: I think to know that Android's location services use GPS signals combined with GSM poles.

On June 2 we walked in Le Mans (France), on the quays of the Sarthe river, area wide open to a relatively wide river; at the other side of the road some trees

The blue arrow lines are collected by GPS E, the pink line is wat Renkforce made of it

(the green/yellow lines are logged by GPS E too, but that was by car, and at that time Renkforce was't logging anymore, don't ask me why, and all of a sudden it restarted (it's pink line starts near the upper right corner, at a place we never were, the timestamps reveal we were at the blue arrow with the white circle)

What I currently do when really eager to collect a track, is using both the Renforce and GPS E, hoping GPS E is perfect, but if not, maybe revert to Renkforce.  In bad cases (also the case for a few days of our vacation in France in June): combine sections from GPS E with sections from Renkforce).  

Yes, I like to have these tracks as I use them to add GPS tags to my photos. The GeoSetter software makes that easy, and it then also adds city names etc to the photos.  But, if I have no tracks, I must do that manually... remember where I took a photo, find it on a map, etc ... labour intensive.

Kris Buelens,
     --- VM/VSE consultant, Belgium ---
-----------------------------------------------------------------------

Op za 19 okt 2024 om 16:35 schreef Kris Buelens <kris.b...@gmail.com>:

[nhoe...@sinet.ca]

I periodically run into situations where it takes a while for my phone to establish a GPS lock, especially if visibility of the GPS satellites is restricted such that the GPS signals are weak.  Moving can delay or even prevent getting a GPS lock under these conditions.  Google Location Services sometimes falls back on cell or network (WiFi access points) which can be quite unreliable outside of urban areas.  If I want to capture a good track, I use the GPS Essentials Satellites feature to verify that I have a GPS lock with good accuracy.  When I start a track, I verify that the summary information looks reasonable and that the track below the summary looks good.  Even if Satellites shows a good GPS lock, going to Tracks and starting a track may require that another GPS lock be established.  Tapping on the map at the bottom of the track summary shows the normal 'map' view where I have included the latitude/longitude, location provider, and accuracy.

[nhoe...@sinet.ca]

What is your Google Location Services/Location Accuracy set to?  In the past, I had set GPS Essentials to "Use Fused Provider" enabled.  With Location Accuracy enabled, that would include other sources of location information, such as cell towers and WiFi access points.  However, after upgrading to a new phone, GPS Essentials is set to "Track only GPS locations".  I recall that unless an app requests GPS information, Google Location Services will typically rely on other location sources to reduce battery drain.  Also, what is your GPS Essentials Update "GPS Update Interval" and "Tracking Update Interval" values?  If  Renforce gets better GPS locations, the problem may be your phone's GPS or where you carry your phone that prevents good visibility of the GPS satellites by your phone's GPS antenna.

[Kris Buelens]

Thanks for your answers.

So, you mean indeed that it is recommended to verify a GPS lock is found before starting the trip and start moving.  Something I indeed do not verify, except yesterday with my first test track.

My settings:
- Android: Location precision: Wifi and Bluetooth are both turned on
- GPS and tracks updates are both set to 5 seconds
- "Track only GPS locations" is selected
- "Use Fused Provider" is not selected

You seem to say that Renkforce would get a better GPS signal.  Seems not my case.  The one I've got is GPS Data Logger GT-730  Look at the very shaky track in Le Mans in a previous post.  And I often had similar problems on other days during that trip to France.
But, I must admit, I returned that device to the webshop and got my money back (a friend suggested I might have gotten an accidental bad logger).
Since a few weeks ago I have a new GPS Data Logger GT-730 but I didn't use that yet on real, multiday, trips.  Just once during a bike trip with my wife and you made me curious, so I had a look with the GPS Track editor that displays both.  The orange line is again Renkforce, with arrows GPS E:

Renkforce around my neck, phone in my trouser's pocket, no clothing with any iron (mostly cotton).  The color of the arrow lines varies with the speed, blue is slow, green a bit faster (too fast for walking, so our bikes)

Again, when houses are in the neighbourhood, Renkforce starts to divert.  And I perfectly remember: houses with only 1 story, near that church (upper right), the sky was quite open, not below trees; GPS E did a very good job.  One can even see we walked past the church to a smaller chapel.   Here Streetview of that village's market:

https://www.google.com/maps/@50.7880293,4.8378472,3a,75y,39.88h,97.41t/data=!3m7!1e1!3m5!1syvnE-31-zd23vEtic7KXXQ!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fcb_client%3Dmaps_sv.tactile%26w%3D900%26h%3D600%26pitch%3D-7.410841381370162%26panoid%3DyvnE-31-zd23vEtic7KXXQ%26yaw%3D39.878659312043894!7i16384!8i8192?authuser=0&coh=205410&entry=ttu&g_ep=EgoyMDI0MTAxNi4wIKXMDSoASAFQAw%3D%3D

The left part of the image: a small street with a few trees, but surely not a wood.  Renkforce is already disturbed, GPS E not.

https://www.google.com/maps/@50.7874306,4.8332511,3a,75y,130.61h,90t/data=!3m7!1e1!3m5!1sBfb5jPnuf8VfC0IBDy2F9Q!2e0!6shttps:%2F%2Fstreetviewpixels-pa.googleapis.com%2Fv1%2Fthumbnail%3Fcb_client%3Dmaps_sv.tactile%26w%3D900%26h%3D600%26pitch%3D0%26panoid%3DBfb5jPnuf8VfC0IBDy2F9Q%26yaw%3D130.60766193396216!7i16384!8i8192?authuser=0&coh=205410&entry=ttu&g_ep=EgoyMDI0MTAxNi4wIKXMDSoASAFQAw%3D%3D

Kris Buelens,
     --- VM/VSE consultant, Belgium ---
-----------------------------------------------------------------------

Op za 19 okt 2024 om 20:00 schreef 'nhoe...@sinet.ca' via GPS Essentials <gpsess...@googlegroups.com>:

Kris Buelens,
     --- VM/VSE consultant, Belgium ---
-----------------------------------------------------------------------

Op za 19 okt 2024 om 20:00 schreef 'nhoe...@sinet.ca' via GPS Essentials <gpsess...@googlegroups.com>:

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[nhoe...@sinet.ca]

Your GPS Essentials settings are similar to mine, although my tracking interval is 10 seconds - I normally use GPS Essentials when walking.  It is not clear why the Renkforce tracker sometimes gives better results than GPS Essentials, and sometimes note.  Maybe it acquires a GPS lock faster but is more sensitive to multipath interference when the GPS signal bounces off large structures.  I recall using apps like GPS Test and GPS Status&Toolbox years ago when phones had weak GPS support.  I remember having to stand in one spot with with clear visibility of GPS satellites and holding the phone still for over 30 seconds to get a GPS lock.  Since then phone GPS chips have improved dramatically but there are still days when weather conditions and the position of GPS satellites in the sky can delay getting a GPS lock or cause GPS locations to jump around.  If the phone moves a significant distance (I cannot quantify 'significant'), it can also delay getting a lock although A-GPS can help (https://en.wikipedia.org/wiki/Assisted_GNSS).  Unfortunately, there are a lot of moving and often invisible parts to getting reliable GPS locations and it can take a while to figure out why GPS is not working as expected.