Comment by WA
This is outrageously wrong. Back in 2011, the pricing model for "an app in your pocket" was 99 cents. The universal pricing model of apps was a one-time fee and the pricing range was that of an mp3 roughly. 30% of that is a lot. App sales worked only in volume.
If you sold software over the internet, you had PayPal, which had a flat fee of $0.35 + 1.7% or so and if your shareware was $30, the transaction fee essentially was ~$1. Stripe had roughly the same fee when they launched. You had more traditional credit card merchants and when I inquired one in Germany back in 2010, it was more or less in the same ballpark (~10%).
In Europe, you could also just get money wired, which cost you something like 0-10 cents.
30% for payment processing were always extremely high.
Edit: The only thing where you had no other options was when you tried to sell stuff on the internet for $1, because the flat fee part of credit card processors would eat up all of that. Apple indeed helped here a little bit, because it was always 30% and no fixed part.
I was thinking about something comparable, where there is a digital storefront, payment processing, security, delivering, installing on all my devices and so on...
Steam comes to mind. They take 30% (and I think 5% for credit card or whatever).
So I do not think that "outrageously wrong" is characterizing my remarks adequately.