Posts Tagged ‘location based services’

notorious

Sunday, December 14th, 2008

The IPhone SDK core location services are notorious difficult to the debug. The documentation is somewhat sparse, the example code works, but what all the parameters really mean and do is not clear. The precision of localization crucially depends on reception, the more towers the better, and, if you are lucky, a clear sky for GPS.

After a first misguided attempt to improve my localization modul (I introduced a cut on the precision of 1km), I went with “take what you get”: ask for the best precision and take the first location, which does not come from the cache. It probably won’t get any better.1 Let’s see how this one works in the “wild”.

1Of course, this not for precision GPS tracking. But for your standard location aware App it should be fine.

bounce back

Saturday, December 13th, 2008

Today (1 day early) Deutsche Bahn changed their mobile webinterface and consequently ZugInfo stopped working. The good news: the changes were minor and I managed to came up with a working version in less then 4h.

I will test the updated version further today and submit it tonight to the App Store. Since this will be a quick fix without my usual 1 week beta testing there might be some bugs left. But given the situation (application not working) I would say it is justified. So, I am looking forward to your bug reports (just attach as comments to any thread or use the mail address from the Impressum page).

On the long run I probably should try to make contact with Deutsche Bahn and see if they can provide a more stable interface. If anyone can help me out with infos or connections, please let me know.

[UPDATE:] The new version has been submitted to the App Store. Expect it beginning of next week.

PS: The last two weeks I have been working on a nearby station feature. I will ship the ZugInfo update with a beta version.

target

Saturday, December 6th, 2008
on spot

on the spot

I am slowly working my way through the IPhone feature catalog. Today on the menu: location based services.

I had my first test go with RegenRadar 1.3. When you read through the manual it sound like a piece of cake: four lines of code. You can get a location like this, true, but what if the user decides to not let you get the location? What is the optimum accuracy? And why is the location manager location not up to date?

See for yourself in RegenRadar 1.3.1. Available soon in an App Store near you.

But location based services do not stop there. Once it’s there, everyone can use it. And querying time tables can be so much more fun when the program knows where you are (as brilliantly demonstrated by Fahrinfo Berlin/Trip Planner and Fahrplan).

my debug console utility - nerd galore

Local public transit is not really the core of ZugInfo (Deutsche Bahn connections is), but according to some of the comments in the App Store people seem to use it exactly for this task.

So I decided to add the “nearby stations” feature. But of course, if you are not interest in this service, you can de-activate in the preferences and will never hear from it again.