A quick post with an Android based UKHAS chase car tracking application.
Fire it up, check the upload URL - set up for Upu's test tracker. Set your chasecar name (whatever_chase), accuracy for GPS/location service (I've set it for being better than 100m), update frequency of attempts to the tracker, and the password to use.
Ticking the top 'Tracking...' check box starts and stops tracking. Being android it can run nicely in the background whilst in the car following the balloon and using copilot/google maps to navigate. :)
android apk here
the appinventor source zip is here - still work in progress
very alpha beta software - any hints, tips or ideas gratefully received either mail or catch me on irc.