Over the Christmas break I went on a road-trip with my Freerunner.  Overall it was a great success.  I used a car USB charger from Jaycar which I have mentioned elsewhere in these forums.  For GPS software I tried both TangoGPS and Navit.

gpsd

For both of the GPS applications below, gpsd needs to be installed.  I installed this from the default repositary using
opkg install gpsd
It installed cleanly and has been running faultlessly.

The built in settings menu GPS toggle seems to control the GPS power only, and does not start or stop gpsd.  I used the mokoservices script installed as part of GPRS configuration process and it seems to work nicely.  I followed the GPRS configuration guide here, using only packages from the default repository. 

Navit

My first preference was to use Navit for navigation and routing.  This was installed from the Navit SVN as described here.  The installation required a number of other packages which were all installed automatically.  Using the default install with the demo maps provided Navit started and displayed a map as expected.

Navit seems to work best with the Open Street Map maps but when I looked at the OSM maps for New Zealand I found them to be very incomplete.  Because I wanted to use this to find out where I was going (as opposed to where I had been) this was an issue so I looked for alternate maps.  The best offerring for New Zealand is the
NZ Open GPS Project who provide free Garmin maps based on the LINZ data.  Navit has some support for Garmon maps so I thought I'd give this a go.  The SVN release seems to have Garmin support compiled in.

I downloaded the gmapsupp.img from the download page, copied it to my SD card and configured the map source in navit.xml as described in the Navit wiki.  I also changed navit.xml to reflect my Wellington starting co-ordinates.

This lead to two results:

  1. Navit took ages (several minutes) to start up and was so unresponsive as to be unusable.
  2. The change to the starting co-ordinates seemed to be ignored.
Thinking that the performance problems were likely to be related to the size of the full NZ map set I downloaded individual maps for the North Island only from here

This resulted in Navit being completely unusable.

At this point I gave up on Navit and decided to look at TangoGPS instead.


TangoGPS

TangoGPS does not provide any routing or navigation function, but will plot your current position on a map and record a track.  This turned out to be extremely useful in itself and helped immensely with navigating unfamiliar cities.

TangoGPS was installed from the default repository using opkg.  Unfortunately it uses the OSM maps that I had already found to be incomplete.  There is a note on the Openmoko wiki entry explaining how to use Google Maps instead of OSM maps, though this may not comply with Google's terms and conditions.  I did it and it worked well.  I configured TangoGPS to use my SD card for storing maps.

You really need to have GPRS working to use TangoGPS as it is unlikely that you will have already downloaded map tiles for every zoom level of every location you want to visit.  I tried to reduce the GPRS requirement as much as possible by installing TangoGPS on my Ubuntu desktop at home and viewing everywhere I could think of that we might need navigation help.  I used the map download function to download multiple zoom levels.  In total there were about 300Mb of downloaded map tiles that I copied on to my SD card to use on the Freerunner.  This was partially successful - many of the maps I wanted were not downloaded even when I was pretty sure I'd covered the area well.  GPRS was still a necessity and for some of the trip no map was possible due to a lack of GPRS reliability or coverage.


In Conclusion

TangoGPS proved to be an excellent and reliable program which performed almost flawlessly the whole trip.  It lacks routing and relies heavily on GPRS if you're out and about but these are not necessarily a hinderance.

Navit also looks like an excellent program but for the lack of OSM coverage of New Zealand.  The best solution for this is for us all to get out there and submit tracks to OSM for inclusion in their maps.  This can be easily done using TangoGPS following these instructions.  In the mean time I'll be following Navit woth the NZ Open GPS maps closely.