Is prepopulating a certain field possible in the mobile Jotform app?

Hi there,

Prepopulating certain fields in the Jotform Mobile App is possible by using the Jotform Prefill Feature.
Select the form you want to prepopulate a certain field, select Edit, and from the Publish Section in the Form Builder select the Prefill Feature.

More details and instructions about prepopulating fields with Jotform Prefill can be found in the following guide:
→ What Is Jotform Prefill and How Does It Work?

If you are referring to the Jotform Apps Feature in your query, the same can be accomplished, because Jotform apps are connected to a form, and you can pre-populate fields in your forms, and by default, they will be prepopulated in the Jotform app when the user is trying to submit the form through the app.

Hope this information helps.
Let us know if you need any further assistance.
Thank you.