Is it possible to collect submissions data offline?

Hello

Is it possible to create a form which will collect data offline, for uploading later once a network connection is available.

JotForm does not have such feature, it is required to have internet connection to submit the data, but you could create a PDF fillable form that may be submitted when your users get internet access. They may start filling it out and save the document, then submit it as soon as they get internet connection. 

This guide will help you creating a PDF fillable form: https://www.jotform.com/help/212-How-to-Create-a-PDF-Form 

Hope this helps.