The ODK ecosystem has been working on specifying an "entities" layer on top of forms. This layer makes it possible to identify the entity that a submission captures data about so that implementing systems can link related submissions and automatically drive multi-form workflows.
This forum post has more on the high-level goals and roadmap.
The current proposed specification is here with XLSForm proposal in this doc.
The ODK ecosystem has been working on specifying an "entities" layer on top of forms. This layer makes it possible to identify the entity that a submission captures data about so that implementing systems can link related submissions and automatically drive multi-form workflows.
This forum post has more on the high-level goals and roadmap.
The current proposed specification is here with XLSForm proposal in this doc.