Develop Bugs

What does GPS actually require to work?

This might be a noob question, but I have a question regarding the GPS.
Does it require data to work? Or does it require data to work for certain GPS features?
I am going to Europe and need to decide if I will need to take my N85 unlocked and try and get a local SIM card there. I want to geotag my photos but don't know if you can since the EVO has no international roaming capabilities.
Does Geotagging (or any other GPS feature) require data to work or can some GPS functions work by connecting directly to the satellites?

pekosROB said:
This might be a noob question, but I have a question regarding the GPS.
Does it require data to work? Or does it require data to work for certain GPS features?
I am going to Europe and need to decide if I will need to take my N85 unlocked and try and get a local SIM card there. I want to geotag my photos but don't know if you can since the EVO has no international roaming capabilities.
Does Geotagging (or any other GPS feature) require data to work or can some GPS functions work by connecting directly to the satellites?
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GPS will require data, especially if you plan on using some form of Geotagging.
Definitely take your N85 unlocked and have a SIM card -- leave your EVO at home, since the EVO is CDMA based and almost all networks in Europe are GSM based, your EVO won't be doing any calling/texting -- that is unless you want to get a huge ass bill for roaming every second?
I'm not 100% positive, but the way it works is that the GPS on the phone will try to connect to your carriers tower first and get all the information it needs from there... then any information it can't retrieve or has to upload (maps, geotag, etc) it'll use a universal satellites. These satellites are the ones that your phone connects to if it has to be tracked if you get lost (via 911) and are also the same ones Google probably uses for Maps, Navigation, etc -- since they provide a large amount of information.
Hope that helps.

pseudoremora said:
GPS will require data, especially if you plan on using some form of Geotagging.
Definitely take your N85 unlocked and have a SIM card -- leave your EVO at home, since the EVO is CDMA based and almost all networks in Europe are GSM based, your EVO won't be doing any calling/texting -- that is unless you want to get a huge ass bill for roaming every second?
I'm not 100% positive, but the way it works is that the GPS on the phone will try to connect to your carriers tower first and get all the information it needs from there... then any information it can't retrieve or has to upload (maps, geotag, etc) it'll use a universal satellites. These satellites are the ones that your phone connects to if it has to be tracked if you get lost (via 911) and are also the same ones Google probably uses for Maps, Navigation, etc -- since they provide a large amount of information.
Hope that helps.
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Above information on GPS is wrong, I am not sure where to start to correct it. Lets not, and simply respond to the original question:
GPS is a global network, and works without any data. In fact a GPS device is receive only device, so it cannot even send. If you have a GPS device, it will work all over the world, though it may take a while in clear sky to get a cold fix for the first time after you crossed the Atlantic.
There is something called AGPS or assisted-GPS, which does use data by first requesting a rough fix from the phone network as well as the current position of all the GPS sats, which will speed up the first fix of the GPS a lot, but that is not needed per se, so if you have no phone signal, or no data roaming, GPS still works, just the first fix may take a bit longer.
Mind you, some phones have a broken AGPS implementation, which behaves strange on some phone networks, so you may want to configure it not to even try to use AGPS when abroad. Have it fall back to regular GPS. Then there will be no roaming or attempted roaming on behave of the GPS. GPS will never provide a (navigation) map, it will only ever give you a position, but for tagging, that is all you need.
As to your specific phones, I do not know the EVO specifically, but assuming Sprint did not put in some program to completely bock the phone when out of its network, since it is Android it will simply let you make pictures and GPS tag them without any network.
You do want to bring your Nokia though if you want to call people, Europe is indeed close to 100% GSM based on the 900 and 1800 Mhz frequencies.

cybermaus said:
Above information on GPS is wrong, I am not sure where to start to correct it. Lets not, and simply respond to the original question:
GPS is a global network, and works without any data. In fact a GPS device is receive only device, so it cannot even send. If you have a GPS device, it will work all over the world, though it may take a while in clear sky to get a cold fix for the first time after you crossed the Atlantic.
There is something called AGPS or assisted-GPS, which does use data by first requesting a rough fix from the phone network as well as the current position of all the GPS sats, which will speed up the first fix of the GPS a lot, but that is not needed per se, so if you have no phone signal, or no data roaming, GPS still works, just the first fix may take a bit longer.
Mind you, some phones have a broken AGPS implementation, which behaves strange on some phone networks, so you may want to configure it not to even try to use AGPS when abroad. Have it fall back to regular GPS. Then there will be no roaming or attempted roaming on behave of the GPS. GPS will never provide a (navigation) map, it will only ever give you a position, but for tagging, that is all you need.
As to your specific phones, I do not know the EVO specifically, but assuming Sprint did not put in some program to completely bock the phone when out of its network, since it is Android it will simply let you make pictures and GPS tag them without any network.
You do want to bring your Nokia though if you want to call people, Europe is indeed close to 100% GSM based on the 900 and 1800 Mhz frequencies.
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I figured I was wrong, I stand corrected.

[Q] Radio 3G issues

This one issue - I will lose data connection even though i have 5 bars - I pop in and out of airplane mode - then have service back. It happens more than a few times a day. My G1 never had this problem. (I don't know if it happens with a voice services)
This issue happens with any program requiring a data connection. Anybody else having this problem - would it be a hardware or software thing? It is not a "deathgrip" thing - since it also happens when its sitting in my car, not in my hand.
Thank you.
Update. Changed battery manager to performance. Noticed that data was only affected. Voice calls still worked. I just want my slacker to work at night.

Well, USA or "other" phone? Reason I ask is because the USA T-Mo version has a wifi calling app that can fiddle with your "preferred network type." At any rate next time it happens you might check that setting for the heck of it. *#*#INFO#*#*, (*#*#4636#*#*). Otherwise maybe your SIM is NFG?

[Q] Possible to use GPS with no network service?

So I'll be in Japan until mid April, and I temporarily discontinued my cell plan. I'm just curious if anyone knows of a way to use the GPS without having any network support what so ever? I mainly use it for an application that tracks the distance and pace that I run, but turn by turn would be nice to have as well. Any help would be wonderful!!

Depends on if the app you have uses a local or network map.. i know with google maps (and maybe google navigation) you can dl map data for use while off network. GPS data is separate afaik (meaning pulling the times from the gps sats to get your location) so that should still work.
Assimilated using the interface that interacts with the advanced internet.

benmatlock said:
Depends on if the app you have uses a local or network map.. i know with google maps (and maybe google navigation) you can dl map data for use while off network. GPS data is separate afaik (meaning pulling the times from the gps sats to get your location) so that should still work.
Assimilated using the interface that interacts with the advanced internet.
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Thanks for the reply. i'm pretty sure i'm out of luck here, Google maps thinks i'm in Hawaii and the wifi I connect to has a mean firewall and I can't get on half the websites I can back home (stupid government). I suppose I can live without GPS. .

simpkill said:
Thanks for the reply. i'm pretty sure i'm out of luck here, Google maps thinks i'm in Hawaii and the wifi I connect to has a mean firewall and I can't get on half the websites I can back home (stupid government). I suppose I can live without GPS. .
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With the Optimus S i had no data connection whatsoever but still manage to get GPS. I used maps to pre-cache the place i wanted to go. It worked well. Just have GPS satellites on under settings.

Try navfee

No GPS signal while making phone call

I recently noticed that neither google maps or waze will keep a GPS lock while I am on a phone call. As soon as the call goes through neither app works but the minute I hang up both apps work properly. Have I turned something off by accident? What has happened?

I have never heard of this before.
I am not aware of any dependence on cell signal for gps to work properly.
I have experienced the functionality of waze and maps not working when on a call as it needs network to update traffic data or plot route changes.
but the GPS never fails.
That being said
Are you on low accuracy which would use cell signal to determine position?
Curious if you have GPS test and when on a call do you still see all the satellites?

parakleet said:
I have never heard of this before.
I am not aware of any dependence on cell signal for gps to work properly.
I have experienced the functionality of waze and maps not working when on a call as it needs network to update traffic data or plot route changes.
but the GPS never fails.
That being said
Are you on low accuracy which would use cell signal to determine position?
Curious if you have GPS test and when on a call do you still see all the satellites?
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Maybe I should have worded it differently by saying what you said...waze and maps stopped working while on a call. It says something like "searching for network".
As far as GPS test...not sure what that is.
Location is set to High Accuracy

clone1008 said:
Maybe I should have worded it differently by saying what you said...waze and maps stopped working while on a call. It says something like "searching for network".
As far as GPS test...not sure what that is.
Location is set to High Accuracy
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Click to collapse
GPS Test: https://play.google.com/store/apps/details?id=com.chartcross.gpstest&hl=en

clone1008 said:
Maybe I should have worded it differently by saying what you said...waze and maps stopped working while on a call. It says something like "searching for network".
As far as GPS test...not sure what that is.
Location is set to High Accuracy
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Click to collapse
That is normal behavior for cell networks that do not have voice and data running simultaneously.
i have experienced waze not coming out of it once data is reestablished, so i have to shut down waze and re open.
ultimately though it is a result of your network not the phone or app.

parakleet said:
That is normal behavior for cell networks that do not have voice and data running simultaneously.
i have experienced waze not coming out of it once data is reestablished, so i have to shut down waze and re open.
ultimately though it is a result of your network not the phone or app.
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I can confirm this. What I do is enable airplane mode and then disable airplane mode to gain data when the call is finished. Stupid carriers

chevelle970 said:
I can confirm this. What I do is enable airplane mode and then disable airplane mode to gain data when the call is finished. Stupid carriers
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It was a real pain last evening. I am away on a business trip. I had just gotten on the highway from the airport in a rental car and my fiance called. Waze stopped working and caused me to miss my exit, I noticed as soon as I hung up from the phone call, waze picked up signal again and started working. I had never had that happen before and I travel frequently.

clone1008 said:
It was a real pain last evening. I am away on a business trip. I had just gotten on the highway from the airport in a rental car and my fiance called. Waze stopped working and caused me to miss my exit, I noticed as soon as I hung up from the phone call, waze picked up signal again and started working. I had never had that happen before and I travel frequently.
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That actually happens to me a lot now that i am on ProjectFI. Never happened with ATT.
My fiance doesnt usually have the issue with verizon, but when she is in a patchy area it freaks her out.

parakleet said:
That actually happens to me a lot now that i am on ProjectFI. Never happened with ATT.
My fiance doesnt usually have the issue with verizon, but when she is in a patchy area it freaks her out.
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Click to collapse
I am on Sprint

clone1008 said:
I am on Sprint
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I have both been on Sprint proper as well as ProjectFi which piggybacks sprint and again what you are describing is in line with the behavior i have experienced.
If projectfi wasnt so cheap i would dump it in a heartbeat for a more robust carrier, Verizon or att

Question Mobile data interruptions on POCO F3 - is there any cure?

Hello, I tried searching on XDA and elsewhere but could not find an answer so I hoping to receive help by writing my issue here.
I have bought two POCO F3's 128GB & 256GB on Amazon & Aliexpress respectively.
They both have the same issue when using mobile data (4g) loading websites and doing voice & | video calls like FB messenger there are interruptions like for a second there is no sound or video freezes. It does not happen on wifi or other phones.
I tried resetting APN, selecting proffered network to LTE, rebooting, switching SIM slot, resetting wifi, mobile and bluetooth settings. Updated both phones to MIUI Global 12.5.1 still no luck.
Country Lithuania (EU) carrier TELE2
We really like the phones, but this is pretty annoying as we do a lot of video calls due to quarantine and what not.
Amazon suggested to replace the phone but seeing as two of them having the same issue it will most likely will not help.
Anyone experienced these issues and came up with solution?

From what u described, seems to me is a bandwidth/mobile data speed problem. Looks like is not enough bandwidth for video call to work properly. So, what is ur bandwidth provided by ISP? What mobile data plan had from ur telephony provider? Maybe ur mobile data signal is low in the place where u make the call from. It can be so many reasons for the issue u confront with, other than a problem with phone itself (a hardware/software issue).

you can also try the latest china stable firmware 12.5.4

Alin45 said:
From what u described, seems to me is a bandwidth/mobile data speed problem. Looks like is not enough bandwidth for video call to work properly. So, what is ur bandwidth provided by ISP? What mobile data plan had from ur telephony provider? Maybe ur mobile data signal is low in the place where u make the call from. It can be so many reasons for the issue u confront with, other than a problem with phone itself (a hardware/software issue).
Click to expand...
Click to collapse
Hi, ty for reply. That should not be an issue, reception is great and we tried it in multiple locations. Our previous devices Iphone 6s/ Poco F1 worked flawlesly with the same carier.
Here is speed test done on mobile data.

Any other ideas?

Found this thread here and I found a solution. Apparently there's an issue with network interruptions in general, especially on phone calls. This can be avoided by switching on VoLTE and WiFi-Calling. This is what I found out over time.
Here's the fun part though: Through a little bit of research this turned out to be a vodafone-problem. I am just guessing you guys will be either also on vodafone or on the corresponding bandwidth in your country.
It seems to be a bug in the F3, but also something that happens when VoLTE is not activated for your SIM card. The phone will try to use VoLTE and this connection will fail, forcing the connection to reset. It will be back in 10-20 seconds, but this is of course super annoying whenever a stable connection is needed (like phone calls...)
Enter *#*#86583#*#* (86583 = VOLTE on dialpad) on your phone. and it will give you a feedback that the carrier check has been disabled. Note that this doesn't mean that VoLTE has been disabled. Checking the network for the capability is disabled then, which makes the setting visible on the SIM card settings. Same works for VoWifi btw.
Try playing around with those settings and see if the connection drops persist. I have no logical explanation why this is happening because what I am telling you is obviously call-related - and I do realize that what you're describing is about the data connection. For me this was related however and solved my issue.
Possible solutions:
a) try to get your service provider to switch on VoLTE for you (this worked for me). You're going to need to call support for that. They will reset your SIM card in the process. Reboot your phone and be done with it.
b) If a) is not possible, deactivate VoLTE in the menu that you activated with the code above. If you're lucky, this will stop the phone from trying to get this type of connection working, even though it's not available. This is broken exception-handling on the phone's side and Xiaomi promised to fix it. They are aware of the bug (since Aug 20th btw) and promised to push a fix into the next MIUI release
c) play with the settings and try to get the phone to not use alternative protocols, just 3G and 4G, also deactivate Wifi-Calling.
Hope this information will help somebody. If all goes well, Xiaomi will fix it and this will behavior will be gone in the next release.

same issue for me with 12.5.7
data interruptions all the time and full signal loss
very disappointed with this device from the day i got it.

O thought I'm the only one facing this problem.
It's so annoying to get an interrupted connection in the middle of the game.

not only game, and calls, i have too much trouble to get throught a call.

Hello all,
i was also affected by a similar issue.
In my case the symptoms were:
On mobile data/5G some apps would be accessing the internet but others wont..
I was able to overcome this by resetting the access point settings and then applying the ones found here:
Cytamobile-Vodafone Cyprus APN Settings for Xiaomi Poco F3 GT - APN Settings
apn.how
I hope it helps...

My fix for this occasional issue is to set the phone to '3g' only in network settings, then flick it back to '5g'. It seems to be area specific for me. Very bizarre.

ntemis021 said:
not only game, and calls, i have too much trouble to get throught a call.
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Click to collapse
I have the same problem, it helps to have the settings volte and vowifi enabled. Sometimes it looks low cell signal and loosing the connection.
Has anyone return for service the device?

It looks like we still have this problem, my F3 modem is crashing every few hours especially when it switches bands, very annoying.

Magister54 said:
It looks like we still have this problem, my F3 modem is crashing every few hours especially when it switches bands, very annoying.
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It really is! We need a bug bounty for this

Hey I ran into the same problem in Hungary Vodafone Poco F3, 14.07 MIUI
4g net is working flawlessly but
Network connection is lost when start dialing
Nobody can reach me on phone
Enter *#*#86583#*#* (86583 = VOLTE on dialpad)
VoLTE select option turn on/off
Enter *#*#869434#*#*
VoWiFi select option turn on/off
I tried to switch on/off both but no solution just yet
sby has answer for this?
Where should I post this problem to be solved?

I also have this problem and I am from Iran. My mobile ROM is the global version. It seems that this problem is caused by the Poco F3 mobile hardware itself. If anyone finds a solution, please let me know, thanks.