From what we know, Cinco uses the following components:
Coffeescript Stitch Backbone Eco Zepto
see comment on http://37signals.com/svn/posts/2761-launch-basecamp-mobile
I believe Cinco has custom models, controllers, collections, views and other helpful tools. see https://gist.github.com/854250
It supports several devices like:
iPhone OS 3.x, Browsers with Google Gears support (Android, Windows Mobile), Blackberry Devices (8820, 9000,...), Nokia Web Run-Time (Nokia N97,...), webOS Application Platform (Palm Pre), Torch Mobile Iris Browser, Mozilla Geode,