Welcome to the Airtable community!

Do you have a free or plus workspace? If so, you will probably need to upgrade to a Pro workspace in order to continue developing a custom app.

Airtable initial gave everyone the ability to use scripts and custom apps, so that people could try out these new features before they became paid-only features. The deadline for when these features became restricted to paid only users has been pushed back a couple of times, so we cannot be completely sure if the deadline will be enforced this time or not. This thread has some of the history as it relates to Scripting App.

Thanks, @kuovonne! I appreciate the information. Yeah, I guess I need to upgrade to Pro.

Or maybe not. There is an update on the thread stating that you will be able to continue custom app development for free for six more months. However, if you can afford Pro, I recommend upgrading to it anyway. You get a wealth of other features with a Pro workspace.

@kuovonne linked to the other thread already, but wanted to share a note here as well that we’re extending the free period for the scripting app (as well as the blocks SDK for creating custom apps) for another 6 months so this period will be extended.