Principle? This subscription milking is getting really old. Look, I get if they charged for Spark because its email and goes through their servers. If they charged $50/year, ok, not my cup of tea to pay for an email app (look at Newton, people paid by the year and no app updates in 5+ months, inexcusable) but I get using their servers that cost money.
What does a PDF "cost?" What resources of theirs are being used? If they can't make money n the old way of about $20 up front then their business model is the problem.
Is iOS PDF software REALLY worth say $200 over 4 years (total cost of ownership)? They somehow were content with $20 up front for many many years and didnt go under offering at that price. If they wanted to charge another $20 for version 7, ok. You can stay on 6 and not upgrade or pay for 7 upgrade; that's fair. App updates to new versions shouldn't be totally free on a paid app, that much I agree.
The $ was already on the high end for an iOS app to begin with (considering the Mac version is $80 too)
I've also stopped using Readdle apps lately, back to stock iOS and if I need something to seriously edit PDF use PDFelement which has similar features to PDFexpert. Same principle why I will never touch Airmail again (despite beta testing for them since the begining too) who threw their customers under the bus who already paid for the app up front to switch to subscription; they wont get another dime from my wallet. Speaking with my wallet as everyone likes to say.
The whole subscription model nickel and dime for everything is getting tiresome and $50/year for PDFs is far far too much money.
