Well, there’s Runtime Revolution, which became Livecode (look up the Wikipedia article to see the compleat list of corporate renamings):
but I don’t think Apple lets them put it on an iPad.
I’ve been using Nodezator (for Python), but not sure if it would run in Pythonista or no.
Lots of other projects in this space — Ryven seems nice:
but again, no iPad version
I’d really like to see a nice tool for making a graphical interface which didn’t have so much baggage.
Of course, the big reason we’re in this position is Bill Gates:
Arguably the best option is AppleScript Studio (or whatever they’re calling writing AppleScript in XCode these days), but again, no XCode for iPad.
FWIW, folks have been wanting this for over a decade: