MySQL Data to ODK Agregate

Welcome to the ODK forum, @htuser ! We're glad you're here. When you get a chance, please introduce yourself here. I'd also encourage you to add a real picture as your avatar because it helps build community!

Longitudinal data collection support in ODK is something that is on the roadmap:

You might also take a look at ODK-X for some of the more advanced functionality that you're looking to implement.