Of course, that's a claim from Apple in response claims of anticompetitive behaviour.

I find it difficult to believe, as a mobile developer myself, that 330,000 jobs are being supported by the App Store in any meaningful way.

Sounds about right to me.

Fermi estimate:

apps-not-abandoned * average-developers-per-app-this-year ~> 2 million apps * 2 developer-months ~> 333,000 developers

UK jobs.

I know "meaningful" isn't well-defined, but more than 1% of the entire UK workforce is not dependent on the App Store (that couldn't be replaced by any other app marketplace)

Ah, I missed that. That does make a difference, and I could only justify it in the unlikely event of a decent percentage of those apps being for businesses specifically dependent on iOS apps in particular rather than mobile phones and websites in general.