From openXdata-users mailing list post

Server & Form related

  • Maximum number of studies: 127
  • Maximum number of form definitions in a study: 127
  • Maximum number of pages in a form definition: 127
  • Maximum number of questions per form definition: 255
  • Maximum number of skip rules per form definition: 127
  • Maximum number of validation rules per form definition: 127
  • Maximum number of questions of type “Single Select Dynamic” per form definition: 127
  • Maximum number of conditions per validation rule: 127
  • Maximum number of conditions per skip rule: 127
  • Maximum number of questions that a single skip rule can affect: 127
  • Maximum number of child questions that a “Repeat” question type can have: 127
  • Maximum number of options (possible answers) that a “Single Select” or “Multiple Select” question type can have: 127
  • Maximum number of forms of data that can be collected per study:2147483647
  • Maximum number of users: 127

Phone related

  • Minimum CLDC version: 1.1
  • Minimum MIDP version: 2.0
  • Maximum jar file size: 128kb
http://groups.google.com/group/openxdata-users/browse_thread/thread/305d43659094a18b/9527b264cc27d414