HTML and CSS: a good sense of web UI design and the ability to implement it across the various browsers is key!
Ruby On Rails: a good understanding of the MVC architecture is crucial. Experience with a comparable web MVC framework is okay, but willingness to learn Ruby and Rails is essential.
2+ years working on professional or personal web application projects
Illustrator - Web designer skills
Mobile Web: we will continue to extend our website to work on various mobile phones. Some experience with web development on the iPhone, Smartphones, etc. using iUI, XHTML Mobile, WML, etc. would be nice.
ASP.NET, C#: experience with these technologies will give you more control of every project you work on because a lot of the Loopt's core server logic is written in C#.
BS or MS in Computer Science or related field