Incredibly slow and inaccurate GPS

My own reading of keesj’s post (which of course is pure guesswork on my side) was that he compared EPO only with EPO and A-GPS. As I already mentioned above, I have both EPO and A-GPS enabled and for the last few months (before upgrading to 1.8) have had no problems with getting fixes. Earlier I do have had the same experience as @humorkritik - when enabling GPS after a long journey it takes some time. Not the other week, though, when turning GPS on after a 130 km trip, I got a fix almost instantly.

I use “GPS status” (https://play.google.com/store/apps/details?id=com.cochibo.gpsstatus). You have a lot of similar apps that do the same that work as well.

In my case, GPS worked well in the beginning, then suddenly was very slow and inaccurate. With the app, I now know when the signal is ready. Sometimes I reset the gps-data or download extra data, if my gps-signal takes too long or is wrong.

I noticed no difference in selecting Google or Nokia where you can choose between those two.

Appart from, in my case, a far better response and first fix time in 1.8 than in 1.6, i found that my phone had a much faster fix when it was NOT being charged in the car. I than wrapped the cable around a ferrite ring and the fix was faster and more stable.
Using the aboce mentioned GPS status i can see the signal strenth of the sats is better when using the more ‘noice free’ charge cable.
Hope this helps as well.

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My experince is: since I have 1.8 I get a quasi immediate and accurate fix.
I am now very happy

Hey…I wonder why nobody in this post recommended the following app (as *.apk available), which a FP user directly programmed for other FP users:
https://f-droid.org/repository/browse/?fdid=de.b0nk.fp1_epo_autoupdate

It can update the EPO files e.g. every 24hours (via WLAN or DataConnection) in order to have everytime the most up-to-date positions of the GPS satellites. Without this app the FP android version is not able to download this file relieable, which causes the problems.

I tested this nice, small piece of software now for more then 3 months (the very first version) and my result:
If I am outside with a moderate view to the sky I repeatedly get a first GPS fix within 15s (A-GPS is disabled), also if I travelled some 10-100 km or didn’t use the GPS for some days-weeks.

Give it a try, report back in some time and if it works recommend it.

Cheers, Robert

This is the reason why:


(The following posts are also interesting to read!)

@Stefan, @keesj :
OK, I missed to read this post, but anyway I claim this is not true, because:

–> correct!
The problem is here:

–> not correct!
The reason, that FP decided to disable the Android standard EPO usage in v1.8 resulted from problems of downloading the EPO files automatically from the Mediatek servers and apply the correct checksums.
Therefore the TimeToFirstFix is incredibly slow (>1min), because there are in deed no actual values for the satellite positions.

Exatly this problem circumvents the “FP1-EPO Autoupdate, by downloading the EPO files correctly, fast and with desired time intervals.

If you update regularly and automatically (in my case every 2 days) I never had a TimeToFirstFix of more than 30s, when beeing outdoor, normally about 12-15s.
During GPS usage I always disabled A-GPS as well as data connection.

You can read all the details on F-Droid and the linked XDA post.

If anybody does not agree: please give it a try and report back here about your experiences!
Cheers, Robert

Hi @therob are you saying that the current “1.8” http download is still failing on the checksum?
I already stated why we disabled the EPO download

@keesj: YES! I would state this, wehn using the build-in Android EPO download.

As far as I know the problem are at the side of the mediatek servers, where the MD5 checksums are wrong calculated! Therefore Android is thinking they are corrupted and trying again to download until it gaves up.

Otherway round: because of the problem with the EPO checksum, FP developer decided to completely turn-off the EPO download in v1.8. ( @anon90052001: correct me If I am wrong)

The “FP1-Auto-Update.apk” calculates his own MD5 checksum and therefore do not have this problem!
You can read more details here, which I already posted above.

Cheers, Robert

Just out of curiosity: if the MediaTek servers calculate the checksums wrongly, why on earth don’t they fix this? I would assume this would affect all MediaTek devices then - and they claim that’s about 30% of the Android market?

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My EPO update experiences:

  1. Right from the beginning, I turned off the automatic update function. I almost always disable all automatic updates on all computer-related stuff, partly to avoid unwanted data traffic, partly to be in control of my gadgets.
  2. Under previous FP OS versions, right up to and including 1.6, updating the EPO files manually has been more or less impossible (after twenty-something attempts it has sometimes worked). The FP1-EPO app solved this problem.
  3. After upgrading to 1.8, the built-in manual update function works perfectly, no doubt because of the switch from FTP to HTTP as described by @keesj here. So the FP1-EPO app is therefore not necessary.
  4. I have not noticed that enabling (updated) EPO files delays getting a first fix. On the contrary: I normally get a fix within 15-20 seconds, while it takes longer if I disable EPO.

This tip is a great tip. Now I understand why the gps is so slow in the car, but works fine outside. In the car I always connect the power. I tried it in the car without the usb power cable, and yes, a quick fix.
I always thought the metal roof of the car messed things up, but alas…
Now I just need to get a ferrit ring.
thanks a lot for the tip.

An alternative (easier) solution that might help:
With the Xposed framework and the GravityBox Module you can choose a 360 degree screen rotation, meaning that you can turn your phone upside down so that the power cable is attached at the ‘bottom’. Thus the interference may be reduced.
More about GravityBox here

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Hello lovely people, I also have a pretty slow and often somewhat inaccurate GPS signal. I bought the latest Fairphone in Germany in January 2015. I only know EPO as a blood doping agent and I am generally clueless about anything involving computers, cell phones and remote controls. Is there any chance you can explain step by step what I need to do to get a better signal? My running app won‘t even work properly. Sigh.

Thank you so much, smart people! <3

this forum is only about the Fairphone, so either you have mistyped or you are in the wrong forum.

if you indeed have a fairphone you could install following apps to help your phone get a GPS fix faster:

  • FP1-EPO-Autoupdate to automaticly get those mysterious EPO files. (I don’t know what they are exactly either).

  • FasterGPS: after installing this app you need to run it and enterthe country you’re in.

  • if you do have Google Services on your phone you can allow Google to locate you with Wifi & mobile connections (System Settings > Location access), if you don’t you can install µg Unified Nlp to get a similiar but free service.

If you have an iPhone and GPS doesn’t work well there you’re pretty much screwed. :wink:

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Thank you Paul. So I just download one of the Apps in the Play Store? Which one do you prefer? I don‘t have all the google systems running (not a fan of google - unfortunately the app store is by google, mäh).

well if you have the play store you (unfortunately) have all of googles services on your phone.
so the third app isn’t necessary for you. I’d install both the other apps and then restart the phone.
when you test your gps be sure to be outside.

Yes now it works normally !!
The solution was simply to unplug the in-car charger.

The difference in signal strength can be easily seen using “GPS test” app : signal bars are divided by 2 when charging and some satellites disappear !

I tried with a randomly chosen ferrite bead on the charging cable but it is the same.
Using an USB port of my battery-powered laptop gives the same result.

Can some of you do the same test with “GPS test” app and tell me if they see the same attenuation in signal strength when charger is connected ?

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Me too.
It is reproducible - as soon as I connect a charging cable in my car, the GPS signal weakens; as soon as I unplug the cable, GPS sattelites begin to appear again, no matter which end of the charger I disconnect. Seems the power intake creates a noise for GPS antenna?

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It seems to me like plugging in earphones also slows down the process of getting a GPS fix. Can someone reproduce this?