The Developer's Guide. Opendatakit - Project Hosting on Google Code. This site is primarily for developers.
If you are not a developer, please visit Open Data Kit (ODK) is a free and open-source set tools which help organizations author, field, and manage mobile data collection solutions. ODK provides an out-of-the-box solution for users to: Build a data collection form or survey; Collect the data on a mobile device and send it to a server; and Aggregate the collected data on a server and extract it in useful formats.