Author of article here. This is a link to a blog post about the technologies used in Killermatch (<a href="http://www.killermatch.com/?cid=hn" rel="nofollow">http://www.killermatch.com/?cid=hn</a>), a racket sports match diary and details which technologies were used, and why. I know many startups are struggling with similar questions, so maybe there is something to be learned. I'll try to answer whatever questions I get here as well.