"Substantially assist" means it provides a substantial portion of the code or other assets for the app, saving some time for the app developer(s). As with a human software engineer, initially providing buggy or useless code and then revising it to be correct and usable after some additional prompting, counts as "assisting".

$5,000 total revenue counts, even if it takes many months. Revenue from all revenue sources attributable to the app counts, including in-app advertising.

 to a large language model, and is not partially or wholly 

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