Lauren Goode, writing for The Verge:

One of the common complaints made by software developers who spoke to The Verge is that they can’t offer free trials of their apps as part of the App Store download process, or issue paid upgrades to long-term users. Others say that selling apps through the App Store can create a kind of wall between them and their customers if the customers have issues with their software. Broadly speaking, the iPad Pro is forcing them to rethink their monetization strategies.

This is something that Apple really needs to address soon. I love the idea behind the App Store’s simplicity, but the business models it allows for aren’t viable for every developer.