Open Data Kit
Open Data Kit (ODK) is a suite of tools to help organizations collect, aggregate and visualize their data. Our goals are to make open-source and standards-based tools which are easy to try, easy to use, easy to modify and easy to scale. To this end, we are proud members of the OpenMobile Consortium, the OpenRosa Consortium, and active participants in the JavaRosa project.
ODK tools used all over the world and ODK Collect is our most popular. Below is a demo video that demonstrates some of its core functionality. There is also an IEEE Computer paper, University Week article, a set of overview slides, and a Google Faculty Summit video that discusses our work more broadly. Finally, there is curriculum from a computer science course at the University of Washington about ODK.
(source: official website)
MobileActive.org review: http://www.mobileactive.org/mobile-tools/open-data-kit; MODI Research group article: http://modi.mech.columbia.edu/2010/04/open-data-kit/