Show HN: Hot & Cold game in mobile web browser

After reading Mark Pilgrims "Dive into HTML5" (currently available at http://diveintohtml5.info) I wanted to play a little with the new API features. I started with Geolocation API, which actually is not a part of HTML5 specification. My main goal was to check if browser geolocation performance is sufficient to work in realtime tracking applications. So I created this simple game, to be used in web browsers on mobile devices. I hope you know Hot & Cold scout game (http://www.scoutorama.com/activity/activity_display.cfm?gm_id=131)? Try it now with your mobile phone here:

http://biesiad.github.com/hotncold

I would be happy to hear your feedback and any ideas for more 'serious' implementations.