10 Replies Latest reply on Jun 4, 2014 2:24 PM by guy@guym.com

    GPS Lag

    PhilProctor

      Title

      GPS Lag

      Post

           I've noticed that Filemaker Go has past GPS locations more often than not.  I'm sequentially adding points with the LocationValue function as a calculation in a field.  The location recorded is usually the location of the last point.  I have the time set for 10 seconds and the accuracy to 35 meters, so it's not very restrictive.

           I wonder why Filemaker Go wouldn't use real time locations like most other apps do?

            

        • 1. Re: GPS Lag
          TSGal

               Phil Proctor:

               Thank you for your post.

               FileMaker Go currently uses the iOS application programming interface (API) to obtain the location.  Other applications may provide more accurate GPS information, but FileMaker Go will not access those applications.

               With that said, in my environment, I have not experienced the issue of the location of the last point being used.  I can walk around our building, test it every 10 seconds, and I do get different values each time.

               Regardless of my results, I recommend that you enter the suggestion (use better GPS information) into our Feature Requests web form at:

          http://www.filemaker.com/company/contact/feature_request.html

               The entries into this web form populate a database that is hosted by Product Management and Development.  All entries are discussed and considered for possible implementation in a future release.  Although I could copy your post and paste it into the web form, there are a couple of questions asked on the form that only you can answer.

               TSGal
               FileMaker, Inc.

          • 2. Re: GPS Lag
            philmodjunk

                 And it may be an iOS issue.

                 When using the Map app, not FMGO,  I have on several occasions noticed that the app seemed either off or behind by as much as a city block and my wife's iPhone has been known to give out a completely "wacky" string of directions that keep changing in nonsensical ways and seem to indicate a continuous update of completely wrong GPS coords.

                 It's left me with a less that solid confidence that a GPS location value captured and recorded in FM GO will be accurate in every case...

            • 3. Re: GPS Lag
              PhilProctor

                   Thanks for the response.  I would suggest trying it and checking the coordinates.  The problem is occurring about 60% of the time and this is so far over about 2,000 points.  The coordinates posted by Filemaker do normally change each time.  There is normally a few minutes between each record, which is what makes it odd.

                   I'll post it in Feature Requests.

              • 4. Re: GPS Lag
                NancyElliot

                     We also experience this lag issue - I do believe it may be associated to iOS as we have tried on different versions.

                     Having said that, I typically have to wait around a minute to get a unique GPS reading. It would be useful to have a refresh or reset function.

                • 5. Re: GPS Lag
                  guy@guym.com

                       It is a known problem...iOS is not suitable for any mission-critical location services.

                       Everytime GO executes (Get Locationvalues), it is asks the iOS to get the data.  Apparently, it does not refresh, but may get from a buffer.

                       All GPS apps have the same issue, by cycling app shows my speeds varying a bunch.  At car speeds, it is not as noticeable, but pedaling in soft sand, my speeds are way out of kilter.

                       I tried ELF GPS dongle with no better results as GO does not talk to ELF, but the iOS.

                       I tied to make an app that would help find underground fixtures (lawn sprinklers) and tell me how far to go for a specific valve.  HA...not even close.

                       My old laptop with Microsoft GPS dongle was much closer, but I'm not good at Windows apps.

                  • 6. Re: GPS Lag
                    PhilProctor

                         TSGal, could you give me a status on a fix for this issue?

                          

                         Thanks

                    • 7. Re: GPS Lag
                      TSGal

                           Phil Proctor:

                           Nothing has changed.  FileMaker Go is currently using iOS 's API to obtain the location.  No other information is available.

                           TSGal
                           FileMaker, Inc.

                      • 8. Re: GPS Lag
                        PhilProctor

                             TSGal

                             I don't know if you understand the severity of this problem whatever its source.  This is the type of bug that should be sitting on your SVP's desk right now for two reasons:

                             1 - It renders FM Go almost useless as a field data collection tool, which also bleeds over into the entire FM family.

                             2 - It creates a liability for FM when users are getting location accuracies reported as being typically better than 20-30 feet when they are frequently several hundred or thousands of feet off.  

                             I'm surprised if it's not on an SVP desk after all of the ramifications after the Apple Map issue.

                             I'd love to here some effort of progress, as we will have to move in a different direction if there's no indication of such.

                             Thanks

                        • 9. Re: GPS Lag
                          TSGal

                               Phil Proctor:

                               The information has been sent to Development.

                               FileMaker, Inc. does not discuss future product releases.

                               TSGal
                               FileMaker, Inc.

                          • 10. Re: GPS Lag
                            guy@guym.com

                                 Well TSGal, if you're walking around in your building, are you getting GPS or Assisted locations.  GPS does not work inside buildings.  If you're getting assisted locations, how do you know they are even close to accurate.  Tri-lateralization and router signals are not known for accuracy.

                                 Other apps are not any more accurate if they are using Assisted locations. I have a test app I'd be glad to share with you (it's on my server), send me an email and I'll send you the link (filemaker domain only).

                                 It runs any number of iterations as you move about, you can set the pause, accuracy, timeout, iterations.

                                 Try it outside as you're walking to your car.  It show total distance covered as well as distance at each iteration.

                                  

                                 guy@guym.com